TRUSFLUKS

Indications

• Dry eye conditions
• Tear deficiency
• Keratoconjunctivitis sicca

Dosage

Children: Apply as required, typically in the form of eye drops.

Adults: Apply as required, typically in the form of eye drops.

Mechanism of action

Hypromellose acts by forming a viscous gel upon contact with the ocular surface, which helps to retain moisture and protect against irritants. This gel-like property enhances the stability of the tear film and reduces evaporation, thereby alleviating symptoms associated with dry eye conditions.

Pharmacodynamics

The pharmacodynamic effects of hypromellose are primarily related to its ability to mimic natural tears, providing lubrication to the ocular surface. This lubrication reduces friction during blinking and maintains corneal hydration, which is critical for ocular comfort and health. Its high viscosity also contributes to prolonged retention time on the eye surface.

Pharmacokinetics

Hypromellose is administered topically as eye drops and is not significantly absorbed systemically. The retention time of hypromellose on the ocular surface is enhanced due to its viscosity, allowing for extended relief of dry eye symptoms. The elimination of hypromellose occurs primarily through drainage from the eye and dilution by the natural tear fluid.

Adverse effects

• Temporary visual disturbance
• Eye irritation

Precautions

• Should not be used during contact lens wear
• Use with caution in patients with known hypersensitivity to any component of the formulation

Pregnancy

Hypromellose is generally considered safe for use during pregnancy. However, it should be used only if clearly needed and after consulting a healthcare provider.

Breast-feeding

Hypromellose is unlikely to affect breastfed infants when used as directed, but consultation with a healthcare provider is advisable.

Storage

Store in a cool, dry place away from direct sunlight. Once opened, use within a specified period as indicated on the packaging.

Formulations

• {'name': 'Teardew', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Xailin Hydrate', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'AacuLose', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Artelac', 'concentration': '0.32%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Lacrilube', 'concentration': '2 mg/g', 'form': 'eye ointment', 'volume': '3.5 g'}
• {'name': 'Celluvisc', 'concentration': '1%', 'form': 'eye drops', 'volume': '0.4 ml unit dose'}

Indications

• Gastroesophageal reflux disease (GERD)
• Erosive esophagitis
• Peptic ulcers
• Helicobacter pylori eradication
• Zollinger-Ellison syndrome

Dosage

Adults: The usual oral dose

Mechanism of action

Esomeprazole exerts its stomach acid-suppressing effects by covalently binding to cysteine residues on the H+/K+-ATPase enzyme at the secretory surface of gastric parietal cells. This action inhibits both basal and stimulated gastric acid secretion irreversibly, requiring the synthesis of new enzyme to restore acid production. By blocking the final step of gastric acid production, esomeprazole reduces gastric acidity in a dose-dependent manner.

Pharmacodynamics

Esomeprazole is a substituted benzimidazole that inhibits gastric acid secretion without exhibiting anticholinergic or H2 receptor antagonistic properties. It is indicated for the treatment of GERD, healing of erosive esophagitis, and eradication of H. pylori to reduce duodenal ulcer recurrence. The suppression of gastric acid secretion is dose-related and effective against various stimuli that promote acid secretion.

Pharmacokinetics

Esomeprazole is rapidly absorbed after oral administration, with peak plasma concentrations typically occurring within 1-2 hours. It undergoes extensive hepatic metabolism primarily by the cytochrome P450 system, especially CYP2C19, resulting in several metabolites. The elimination half-life is approximately 1-2 hours, though its antisecretory effects last longer. It is excreted predominantly in the urine. Dose adjustments may be necessary in patients with hepatic impairment.

Contra-indications

• Hypersensitivity to esomeprazole or any of its components
• Concomitant use with rilpivirine-containing products

Adverse effects

• Abdominal pain
• Constipation
• Diarrhea
• Dizziness
• Dry mouth
• Headache
• Insomnia
• Nausea
• Skin reactions
• Vomiting
• Bone fractures
• Confusion
• Depression
• Drowsiness
• Leucopenia
• Malaise
• Myalgia
• Paraesthesia
• Peripheral edema
• Thrombocytopenia
• Vertigo
• Vision disorders
• Agranulocytosis
• Alopecia
• Gynaecomastia
• Hallucination
• Hepatic disorders
• Hyperhidrosis
• Hyponatraemia
• Nephritis
• Tubulointerstitial nephritis
• Pancytopenia
• Photosensitivity reaction
• Severe cutaneous adverse reactions (SCARs)
• Stomatitis
• Taste altered
• Hypomagnesaemia

Interactions

• Esomeprazole may increase the exposure to cannabidiol
• Esomeprazole may increase the exposure to cilostazol

Precautions

• Increased risk of fractures, particularly in the elderly and when used at high doses for over a year
• Caution in patients at risk of osteoporosis; adequate intake of calcium and vitamin D is recommended
• May increase the risk of gastrointestinal infections, including Clostridioides difficile
• Symptoms of gastric cancer should be ruled out before treatment
• Use with caution in patients with hepatic impairment

Pregnancy

Use with caution. The manufacturer advises avoiding use unless necessary since the effects on the fetus are not fully known.

Breast-feeding

Manufacturer advises avoiding use as esomeprazole is present in breast milk and may cause diarrhea in nursing infants. However, amounts are probably too small to be harmful.

Storage

Store in a cool, dry place below 25°C. Keep out of

Indications

• Skin disinfection
• Preparation of skin before injections
• Cleansing minor wounds

Dosage

Children: Apply to the skin as required; consult product literature for specific guidance.

Adults: Apply to the skin as required for disinfection.

Mechanism of action

Alcohol exerts its antiseptic effect by denaturing proteins, disrupting cell membranes, and dehydrating microbial cells, leading to cell lysis and death.

Pharmacodynamics

Alcohol has broad-spectrum antimicrobial activity, effective against bacteria, fungi, and viruses. Its efficacy is influenced by concentration, with higher concentrations generally being more effective.

Pharmacokinetics

Alcohol is rapidly absorbed through the skin and mucous membranes. It is metabolized primarily in the liver, with a half-life that varies based on the individual's metabolic rate and the amount consumed.

Contra-indications

• Concomitant use with lithium
• Regular use in neonates
• Patients with severe burns when diathermy has been preceded by application of alcoholic skin disinfectants

Adverse effects

• Eye erythema
• Punctate keratitis
• Cytotoxicity
• Eye discolouration

Interactions

• Increases risk of visual disturbances with antiepileptics
• Increases concentration with methylphenidate
• Increases risk of facial flushing and skin irritation with topical pimecrolimus
• Increases concentration with retinoids
• Increases concentration with acitretin
• Increases risk of facial flushing and skin irritation with topical tacrolimus
• Decreases antidiuretic effect with vasopressin

Precautions

• Avoid regular application to inflamed or broken skin or mucosa
• Avoid broken skin
• Flammable

Pregnancy

Sufficient iodine may be absorbed to affect the fetal thyroid in the second and third trimester.

Breast-feeding

Avoid regular or excessive use.

Storage

Store in a cool, dry place away from heat and direct sunlight.

Formulations

• Betadine 2.5% dry powder spray
• Industrial methylated spirit
• Povidone-Iodine 25 mg per 1 gram

Mechanism of action

Acetone acts as a solvent and is utilized in various biochemical pathways. It participates in the biosynthesis of isopropanol and is involved in the degradation pathways where it converts into other metabolites such as methylglyoxal and acetoacetate. It also plays a role in pyruvate fermentation and is integral to the fermentation processes in Clostridium acetobutylicum.

Pharmacodynamics

Acetone has a low molecular weight and is highly volatile, which allows it to penetrate biological membranes easily. Its pharmacological effects are primarily due to its role as a solvent and its ability to influence metabolic processes. Acetone can affect lipid metabolism and may impact energy homeostasis by influencing the balance between fat and carbohydrate utilization.

Pharmacokinetics

Acetone is rapidly absorbed through inhalation and dermal exposure. It is distributed throughout the body and can cross the blood-brain barrier. Metabolism occurs primarily in the liver where acetone is converted into acetoacetate and other metabolites. The elimination of acetone occurs mainly through renal excretion, with a half-life varying based on the route of exposure and individual metabolism.

Pregnancy

Acetone is classified as a pregnancy category C drug. Its effects during pregnancy are not well-studied, and caution should be exercised.

Breast-feeding

There is limited information on the excretion of acetone in breast milk. Caution is advised when using acetone during breastfeeding.

Storage

Store in a cool, dry place, away from heat and direct sunlight. Keep tightly closed in original container.

Dosage

Children: Refer to specific guidelines or consult the BNF for appropriate dosage.

Adults: Refer to specific guidelines or consult the BNF for appropriate dosage.

Mechanism of action

Acrylate acts as a reactive compound that can participate in various biochemical reactions. It may undergo conjugation with glutathione and other biomolecules, leading to detoxification or metabolic transformation. The involvement of acrylate in the metabolism of seleno-compounds suggests a role in the detoxification pathways, where it may facilitate the elimination of harmful substances from the body.

Pharmacodynamics

Acrylate does not have established pharmacodynamic effects as a therapeutic agent, as it is primarily recognized for its industrial applications. However, its interactions with biological macromolecules can lead to cytotoxic effects, especially at high concentrations. It is known to be a skin and respiratory irritant, and prolonged exposure may result in a range of toxicological effects.

Pharmacokinetics

The pharmacokinetics of acrylate in humans have not been extensively studied, but it is known to be rapidly absorbed through the skin and respiratory tract. Once in the body, acrylate can undergo biotransformation primarily through conjugation with glutathione, leading to more water-soluble metabolites that can be excreted via urine. The compound's half-life and distribution in human tissues are not well-characterized.

Pregnancy

The safety of acrylate during pregnancy has not been fully established. It is advisable to avoid use unless deemed absolutely necessary by a healthcare professional.

Breast-feeding

Limited data exist on the use of acrylate during breastfeeding. Caution is advised, and it should only be used if the benefits outweigh potential risks.

Storage

Store in a cool, dry place away from direct light and moisture. Keep out of reach of children.

Indications

• Constipation
• Dietary fiber supplementation
• Irritable bowel syndrome
• Diverticular disease
• Weight management

Dosage

Children: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Adults: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Mechanism of action

Cellulose acts primarily as a bulk-forming laxative. It absorbs water in the intestines, which increases stool bulk and stimulates peristalsis, thus facilitating bowel movements. Additionally, cellulose is not digestible by human enzymes, leading to fermentation by gut bacteria, which may enhance gut health and alter gut microbiota composition.

Pharmacodynamics

Cellulose increases stool weight and frequency of bowel movements. It works by retaining water in the intestines, leading to softer stools and improved passage through the gastrointestinal tract. The bulking effect of cellulose can help alleviate constipation and promote overall digestive health. It may also play a role in cholesterol reduction and glycemic control through its effects on digestion and absorption of nutrients.

Pharmacokinetics

Cellulose is not absorbed into the bloodstream due to its indigestible nature. Instead, it passes through the gastrointestinal tract, where it adds bulk to the stool. Its fermentation by colonic bacteria produces short-chain fatty acids, which may have beneficial effects on colon health. The onset of action for cellulose as a laxative can vary but is generally within 24 to 72 hours after ingestion.

Adverse effects

• Bloating
• Flatulence
• Diarrhea
• Abdominal discomfort

Precautions

• Use with caution in patients with a history of gastrointestinal disorders.
• Monitor for potential allergic reactions in sensitive individuals.

Pregnancy

Cellulose is generally considered safe during pregnancy as it is a non-toxic, indigestible fiber.

Breast-feeding

Cellulose is also considered safe during breastfeeding; it is excreted in breast milk in negligible amounts.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Powder
• Capsules
• Tablets
• Granules

Indications

• Hypovolemic shock
• Severe burns
• Postoperative fluid replacement
• Sepsis
• Trauma management

Dosage

Children: Refer to established guidelines for specific dosing, as it varies based on the type of colloidal solution used and the clinical condition being treated.

Adults: Refer to established guidelines for specific dosing, as it varies based on the type of colloidal solution used and the clinical condition being treated.

Mechanism of action

Colloidal solutions work by maintaining oncotic pressure in the blood, thus helping to retain fluid within the vascular system. This is primarily due to the large molecular weight of the colloidal particles, which cannot easily pass through capillary walls. The presence of colloids in the blood helps to draw water into the circulation, increasing blood volume and improving tissue perfusion.

Pharmacodynamics

The pharmacodynamics of colloidal solutions are centered on their ability to exert osmotic pressure, which helps maintain blood volume and pressure. This effect is particularly important in conditions such as hypovolemia and shock, where fluid replacement is necessary to restore hemodynamic stability. The efficacy of colloidal solutions can vary depending on the type of colloid used, as well as the underlying clinical condition being treated.

Pharmacokinetics

Colloidal solutions are typically administered intravenously and their pharmacokinetics can vary based on the specific formulation. Generally, colloids are distributed throughout the vascular compartment and have a longer duration of action compared to crystalloids, as they remain in circulation longer. The elimination of colloids is primarily through the reticuloendothelial system, where they are metabolized or eliminated by the liver and spleen. Factors such as particle size and composition can influence their distribution and clearance.

Adverse effects

• Allergic reactions
• Injection site reactions
• Nausea
• Vomiting
• Headache
• Fever

Precautions

• Use with caution in patients with known allergies to any component of the formulation
• Monitor for signs of hypersensitivity during administration
• Consider volume overload in patients with cardiac or renal impairment

Pregnancy

The safety of colloidal solutions during pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether colloidal solutions are excreted in human milk. Caution should be exercised when administering to breastfeeding mothers.

Storage

Store at room temperature, protect from light, and do not freeze. Keep out of reach of children.

Formulations

• Colloidal silver
• Colloidal gold
• Colloidal iron
• Other metal colloids

Indications

• Drug delivery systems
• Biodegradable implants
• Controlled release formulations
• Tissue engineering
• Medical device coatings

Dosage

Children: As with adult dosing, paediatric dosing of copolymers is specific to the formulation and application. Consult relevant pediatric pharmacology resources for detailed dosing recommendations.

Adults: Dosing of copolymers is highly variable and dependent on the specific drug formulation and intended use. For precise dosing information, refer to established pharmacological guidelines or product-specific resources.

Mechanism of action

Copolymers can function as drug delivery vehicles, allowing for controlled release of therapeutic agents. They can encapsulate drugs and release them in a sustained manner, depending on environmental triggers such as pH or temperature. This mechanism enhances the efficacy of drugs while minimizing side effects.

Pharmacodynamics

The pharmacodynamic properties of copolymers depend on their composition and structure, influencing their interaction with biological systems. They can modify drug release profiles and enhance the therapeutic effects of co-administered agents, facilitating targeted delivery to specific tissues or cells.

Pharmacokinetics

The pharmacokinetics of copolymers vary based on their molecular weight, structure, and the drugs they carry. Factors such as absorption, distribution, metabolism, and excretion will depend on the formulation and the specific application. Generally, copolymers can improve drug stability and prolong circulation time in the body.

Pregnancy

The safety of copolymer use during pregnancy has not been established. Non-essential use should be avoided.

Breast-feeding

The excretion of copolymers in human milk is unknown. Caution is advised when administering to nursing mothers.

Storage

Store in a cool, dry place away from direct light. Check specific product storage requirements as they may vary.

Indications

• Used as a disintegrant in tablet and capsule formulations
• Enhancement of drug bioavailability
• Facilitation of rapid disintegration of oral dosage forms

Dosage

Children: Refer to the specific formulation guidelines, as croscarmellose sodium is used in varying concentrations depending on the formulation.

Adults: Refer to the specific formulation guidelines, as croscarmellose sodium is used in varying concentrations depending on the formulation.

Mechanism of action

Croscarmellose sodium acts by swelling and forming a gel-like structure upon contact with water. This swelling leads to the rapid breakdown of the tablet or capsule matrix, facilitating the liberation of active pharmaceutical ingredients. The mechanism involves the hydration of the polymer chains, which disrupts the cohesive forces in the formulation, allowing for quicker disintegration and subsequent absorption.

Pharmacodynamics

As a disintegrant, croscarmellose sodium does not exert pharmacological effects on the body but rather enhances the delivery and effectiveness of other active drugs. Its role is crucial in ensuring that medications dissolve properly, thereby influencing the onset of action, peak plasma concentrations, and overall therapeutic efficacy of the administered drugs.

Pharmacokinetics

Croscarmellose sodium is not absorbed in the gastrointestinal tract, as its primary function is to aid in the disintegration of solid dosage forms. After serving its purpose, it is excreted unchanged. The substance does not have a systemic pharmacokinetic profile since it does not enter systemic circulation.

Pregnancy

Croscarmellose sodium is generally considered safe during pregnancy, but consult a healthcare provider for specific recommendations.

Breast-feeding

Croscarmellose sodium is unlikely to pose a risk during breastfeeding; however, consult a healthcare provider for personalized advice.

Storage

Store in a cool, dry place away from moisture and direct sunlight.

Formulations

• Croscarmellose sodium is commonly available as a powder or granule for pharmaceutical use.

Indications

• Used as an excipient in solid dosage forms
• Facilitates drug disintegration and dissolution

Dosage

Children: Refer to specific product formulation guidelines as crospovidone is used as an excipient and does not have a direct dosage.

Adults: Refer to specific product formulation guidelines as crospovidone is used as an excipient and does not have a direct dosage.

Mechanism of action

Crospovidone acts by rapidly absorbing water and swelling upon contact with moisture. This action leads to the disintegration of solid dosage forms, thus increasing the surface area of the active ingredients and promoting their dissolution and subsequent absorption in the gastrointestinal tract. It does not affect the pH of the formulation, ensuring that the active ingredients remain stable.

Pharmacodynamics

Crospovidone exhibits properties that enhance the bioavailability of active ingredients in pharmaceutical formulations. Its ability to rapidly disintegrate tablets and capsules leads to quicker release and absorption of the drug into systemic circulation. As a disintegrant, it aids in the effective delivery of drugs that may otherwise be poorly soluble.

Pharmacokinetics

Crospovidone itself is not absorbed systemically when administered orally. It remains in the gastrointestinal tract, where it performs its function as a disintegrant. The pharmacokinetic profile of drugs formulated with crospovidone may be influenced by the enhanced dissolution and absorption rates provided by this excipient.

Pregnancy

Crospovidone is considered to have low toxicity and is generally regarded as safe for use during pregnancy, but specific studies are limited.

Breast-feeding

There is insufficient data on the excretion of crospovidone in human milk, but it is deemed safe for use during breastfeeding.

Storage

Store in a cool, dry place away from light and moisture, in tightly closed containers.

Formulations

• Powder
• Tablets

Indications

• Oral medications for improved solubility
• Topical applications for enhanced delivery of active ingredients
• Parenteral formulations for intravenous administration
• Vaccines delivered as emulsions for enhanced immune response

Dosage

Children: Refer to specific product information for dosage guidelines, as this varies by formulation and intended use.

Adults: Refer to specific product information for dosage guidelines, as this varies by formulation and intended use.

Mechanism of action

The mechanism of action of a dispersion often involves the physical distribution of active pharmaceutical ingredients in a medium, which can lead to increased surface area and improved interaction with biological membranes. For example, in emulsions, the dispersion of oil in water can enhance the absorption of lipid-soluble drugs.

Pharmacodynamics

Pharmacodynamics of dispersions relates to how the dispersed formulation affects the body. The presence of surfactants or emulsifying agents can modify drug release rates, enhance absorption, and improve therapeutic effects. The effectiveness of a dispersion is influenced by particle size, viscosity, and the nature of the dispersing medium.

Pharmacokinetics

The pharmacokinetics of dispersions depend on the formulation type and the route of administration. Key factors include the rate of dispersion breakdown, absorption through biological membranes, distribution within the body, metabolism, and excretion of the active ingredients. Dispersions can alter the onset of action and duration of effect based on their formulation characteristics.

Pregnancy

Consult with a healthcare provider before use. Safety in pregnancy is not established for all formulations.

Breast-feeding

Consult with a healthcare provider before use. Safety during breastfeeding may vary depending on the formulation.

Storage

Store in a cool, dry place away from direct sunlight. Follow specific storage instructions provided by the manufacturer.

Indications

• Alcohol use disorder
• Acute alcohol intoxication
• Antiseptic for skin disinfection

Mechanism of action

Ethanol affects the brain’s neurons in several ways. It alters their membranes, ion channels, enzymes, and receptors. Ethanol binds directly to the receptors for acetylcholine, serotonin, GABA, and NMDA receptors for glutamate. The sedative effects are mediated through binding to GABA receptors and glycine receptors, while also inhibiting NMDA receptor functioning. As an anti-infective, ethanol acts as an osmolyte, disrupting the osmotic balance across cell membranes. The acute effects result from competitive inhibition of glycine binding to NMDA receptors, leading to disrupted glutamatergic neurotransmission.

Pharmacodynamics

Ethanol produces cellular injury through dehydration and precipitation of cytoplasm, contributing to its bactericidal and antifungal actions. It can lead to neuritis and nerve degeneration when injected near nerve tissues. Up to 98% of ethanol in the body is oxidized, primarily by the hepatic enzyme alcohol dehydrogenase. Its modulation of neurotransmitter receptors, particularly GABA and NMDA, leads to its sedative properties and potential for developing tolerance with chronic use.

Pharmacokinetics

Ethanol is readily absorbed from the gastrointestinal tract and distributed throughout the body. It has a volume of distribution of approximately 0.5 to 0.6 L/kg. Ethanol is metabolized predominantly in the liver by alcohol dehydrogenase to acetaldehyde, which is further oxidized to acetic acid by aldehyde dehydrogenase. The elimination half-life of ethanol varies but is generally around 4 to 5 hours. Factors such as age, sex, body weight, and genetic variability can influence ethanol metabolism.

Contra-indications

• Hypersensitivity to ethanol
• Acute alcohol intoxication
• Severe liver disease
• Pregnancy (in non-medicinal use)
• Severe pancreatitis
• Severe head injury or intracranial bleeding

Adverse effects

• Dizziness
• Nausea
• Vomiting
• Headache
• Sedation
• Cognitive impairment
• Respiratory depression
• Hypotension
• Gastrointestinal bleeding
• Alcohol withdrawal syndrome

Interactions

• CNS depressants (e.g., benzodiazepines, opioids) may enhance sedative effects
• Disulfiram may cause unpleasant reactions when taken with ethanol
• Acetaminophen may increase hepatic toxicity when used with ethanol
• Warfarin may have altered effects when used with ethanol

Precautions

• Caution in patients with a history of alcohol abuse
• Use with caution in patients with hepatic impairment
• Monitor for signs of respiratory depression
• Consider potential for addiction and withdrawal symptoms
• Use in moderation in older adults due to increased sensitivity

Pregnancy

Ethanol should be avoided during pregnancy due to the risk of fetal alcohol spectrum disorders.

Breast-feeding

Ethanol can pass into breast milk; breastfeeding should be avoided for a minimum of 2 hours after consumption.

Storage

Store in a cool, dry place away from light. Keep tightly closed and out of reach of children.

Formulations

• Oral solutions
• Topical antiseptics
• Intravenous formulations
• Medicinal tinctures

Indications

• Alcohol use disorder
• Anxiety disorders
• Sedation
• Muscle relaxation

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines in paediatric populations.

Adults: Refer to the specific BNF guidelines for dosing related to alcohol use disorder and other indications.

Mechanism of action

Ethyl groups serve primarily as substituents in organic chemistry, influencing the properties and reactivity of the parent molecules. In the context of ethanol, which contains an ethyl group, its mechanism of action involves the enhancement of gamma-aminobutyric acid (GABA) receptor activity, leading to increased inhibitory neurotransmission. This results in its sedative, anxiolytic, and muscle relaxant effects.

Pharmacodynamics

The pharmacodynamics of compounds containing the ethyl group, particularly ethanol, include its effects on the central nervous system, where it acts as a depressant. Ethanol enhances the effects of GABA, resulting in sedation, impaired motor function, and decreased anxiety. It can also affect the dopaminergic pathways, leading to the release of dopamine, which contributes to its reinforcing properties.

Pharmacokinetics

Ethanol is rapidly absorbed from the gastrointestinal tract, with peak blood concentrations typically reached within 30 to 90 minutes after consumption. It is metabolized primarily in the liver by alcohol dehydrogenase and aldehyde dehydrogenase, with a first-order elimination kinetics, typically at a rate of 10 to 15 mL of pure alcohol per hour. Ethanol is also known to exhibit a volume of distribution of approximately 0.5 to 0.7 L/kg in adults.

Indications

• Angina pectoris
• Heart failure
• Hypertensive emergencies
• Myocardial infarction

Dosage

Children: Dosing in children is not well established; refer to

Adults: For acute angina, 0.3 to 0.6 mg sublingually. For transdermal patches, doses vary based on the specific product; consult guidelines for individualized dosing.

Mechanism of action

Nitroglycerin is converted by mitochondrial aldehyde dehydrogenase in vascular smooth muscle cells to nitric oxide (NO). NO activates guanylate cyclase, leading to the conversion of guanosine triphosphate (GTP) to cyclic guanosine 3',5'-monophosphate (cGMP). cGMP induces relaxation of vascular smooth muscle, which results in vasodilation and increased blood flow, particularly to the heart. This mechanism reduces myocardial oxygen requirements and alleviates angina symptoms.

Pharmacodynamics

Nitroglycerin causes relaxation of vascular smooth muscles, leading to both arteriolar and venous dilation. This results in increased myocardial blood flow, reduced cardiac preload and afterload, and lowered myocardial wall stress. Additionally, it alleviates coronary artery spasms and decreases systemic vascular resistance and blood pressure. Tolerance may develop with prolonged use, reducing efficacy due to desensitization of smooth muscle and potential inhibition of mitochondrial aldehyde dehydrogenase.

Pharmacokinetics

Nitroglycerin is rapidly absorbed and undergoes significant first-pass metabolism when administered orally. It has a half-life of about 1-4 minutes when given intravenously. The onset of action varies depending on the route of administration, with sublingual forms acting within minutes and transdermal patches providing sustained release. The drug is metabolized primarily in the liver and excreted in urine as metabolites.

Contra-indications

• Hypersensitivity to nitroglycerin or any of its components
• Severe anemia
• Increased intracranial pressure
• Hypotension
• Cardiomyopathy with obstructive lesions
• Severe aortic stenosis

Adverse effects

• Headache
• Dizziness
• Hypotension
• Tachycardia
• Nausea
• Flushing
• Methemoglobinemia

Interactions

• Concurrent use with phosphodiesterase type 5 inhibitors (e.g., sildenafil, tadalafil) may lead to severe hypotension
• Antihypertensives may enhance the hypotensive effect of nitroglycerin
• Alcohol may increase the risk of hypotension
• Other vasodilators may have additive effects

Precautions

• Use with caution in patients with renal or hepatic impairment
• Monitor blood pressure regularly
• Consider potential for tolerance with prolonged use
• Should not be abruptly discontinued after long-term use

Pregnancy

Nitroglycerin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Limited data available.

Breast-feeding

Nitroglycerin is excreted in breast milk, caution is advised when administering to nursing mothers.

Storage

Store in a tightly closed container at room temperature, away from moisture and heat.

Formulations

• Sublingual tablets
• Transdermal patches
• Oral extended-release capsules
• Intravenous infusion
• Topical ointment

Dosage

Children: Refer to specific guidelines for pediatric dosing; consult the BNF for Children for accurate dosage information.

Adults: Refer to specific guidelines for use; dosage may vary based on the context of use.

Mechanism of action

Hydroxide ions act primarily as bases, neutralizing acids to form water and salts. They participate in various biochemical pathways, including selenium metabolism and the degradation of reactive oxygen species. Hydroxide can influence enzyme activity and stability by altering the pH of the environment, thereby affecting metabolic reactions.

Pharmacodynamics

Hydroxide ions can impact biological processes by changing the local pH, which influences enzyme activity, ion transport, and the solubility of other compounds. Their ability to neutralize acids can help regulate physiological pH, contributing to homeostasis in living organisms.

Pharmacokinetics

As an inorganic ion, hydroxide does not undergo traditional pharmacokinetic processes like absorption, distribution, metabolism, or excretion. Instead, it is rapidly equilibrated in biological fluids and participates in acid-base reactions, having immediate effects on the local environment.

Pregnancy

There is limited information regarding the use of hydroxide during pregnancy. Consult a healthcare professional for advice.

Breast-feeding

Limited data is available on the excretion of hydroxide in breast milk. Consult a healthcare professional before use.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Used as an excipient in pharmaceutical formulations
• Improves solubility and stability of active ingredients
• Facilitates drug absorption

Dosage

Children: Refer to specific product guidelines as hydroxypropyl is typically used as an excipient and not dosed independently.

Adults: Refer to specific product guidelines as hydroxypropyl is typically used as an excipient and not dosed independently.

Mechanism of action

Hydroxypropyl functions primarily as a solubilizing agent, which aids in the dissolution of poorly soluble drugs. It interacts with water and other solvents to improve the dispersion of pharmaceutical compounds, thereby enhancing their bioavailability. Hydroxypropyl may also facilitate the permeability of drug molecules through biological membranes, contributing to their overall efficacy.

Pharmacodynamics

The pharmacodynamics of hydroxypropyl relate to its role in improving the physicochemical properties of drug formulations. By increasing solubility and stability, hydroxypropyl can enhance the absorption of drugs administered via various routes, including oral and topical. Its non-toxic nature allows for safe incorporation into formulations, making it suitable for a wide range of applications.

Pharmacokinetics

The pharmacokinetics of hydroxypropyl have not been extensively studied as it primarily acts as an excipient rather than an active pharmaceutical ingredient. When used in formulations, it is typically not absorbed into systemic circulation in significant amounts, thereby minimizing potential systemic effects. Hydroxypropyl is generally regarded as safe when used in appropriate amounts in drug formulations.

Pregnancy

Hydroxypropyl is not classified for use during pregnancy, and its safety has not been established. Caution is advised.

Breast-feeding

There is limited information on the excretion of hydroxypropyl in human milk. Caution is advised when administering to breastfeeding women.

Storage

Store in a cool, dry place, away from light. Keep out of reach of children.

Indications

• Lactose intolerance
• As a filler or excipient in pharmaceutical formulations

Dosage

Children: Refer to the BNF for Children for specific dosing information based on age and clinical context.

Adults: Refer to the BNF for specific dosing information based on clinical context.

Mechanism of action

Lactose is metabolized in the intestine by the enzyme lactase into its constituent monosaccharides, glucose and galactose. In individuals with lactase deficiency, unabsorbed lactose passes into the colon, where it is fermented by bacteria, leading to gas production and osmotic effects that contribute to diarrhea.

Pharmacodynamics

The pharmacodynamics of lactose are primarily related to its effects on gastrointestinal function. In healthy individuals, lactose is effectively broken down into glucose and galactose, which are absorbed and utilized for energy. In individuals with lactose intolerance, the unabsorbed lactose can cause osmotic diarrhea and colonic fermentation, leading to discomfort and symptoms associated with lactose intolerance.

Pharmacokinetics

Lactose is not absorbed in the gastrointestinal tract until it is hydrolyzed into glucose and galactose by lactase. The absorption of glucose and galactose occurs in the small intestine. The half-life is not applicable as lactose is not typically administered as a medication but is rather ingested as a natural component of food. Its metabolism primarily occurs in the intestine.

Adverse effects

• Bloating
• Diarrhea
• Abdominal pain
• Flatulence

Precautions

• Use with caution in patients with lactose intolerance.
• Consider potential for gastrointestinal upset in sensitive individuals.

Pregnancy

Lactose is generally considered safe for use during pregnancy. However, consult a healthcare professional for individual advice.

Breast-feeding

Lactose is safe to use while breastfeeding, as it is a natural sugar present in breast milk.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Powder
• Granules
• Tablets
• Syrup

Dosage

Children: Refer to product-specific guidelines or literature for dosing information, as methacrylic acid is primarily used in industrial and medical applications rather than as a direct therapeutic agent.

Adults: Refer to product-specific guidelines or literature for dosing information, as methacrylic acid is primarily used in industrial and medical applications rather than as a direct therapeutic agent.

Mechanism of action

Methacrylic acid functions primarily as a monomer that undergoes polymerization to form methacrylate-based polymers. The polymerization process can be initiated by thermal, chemical, or photoinitiated methods, resulting in the formation of cross-linked networks that provide structural integrity and durability to the final product. It interacts with radical initiators to form reactive free radicals that propagate the polymer chain growth.

Pharmacodynamics

Methacrylic acid and its derivatives exhibit good mechanical properties and biocompatibility, making them suitable for use in medical and dental applications. The polymers formed from methacrylic acid demonstrate resistance to wear, chemical degradation, and UV light, which enhances their stability and longevity in various environments. The biocompatibility of methacrylate polymers is essential for their application in medical devices, ensuring minimal adverse reactions upon implantation.

Pharmacokinetics

The pharmacokinetics of methacrylic acid is not extensively characterized due to its primary use as a polymer precursor rather than a therapeutic agent. However, when released in vivo, it is assumed to undergo rapid metabolism. The compound is likely to be absorbed through various routes, but specific absorption, distribution, metabolism, and excretion (ADME) data are limited. As a low molecular weight organic acid, it may be subject to conjugation and subsequent elimination through renal pathways.

Pregnancy

Methacrylic acid and its derivatives should be used with caution during pregnancy, as there is limited data on their safety. It is advisable to avoid use unless the potential benefits outweigh the risks.

Breast-feeding

There is insufficient information regarding the excretion of methacrylic acid into human milk. Caution is advised when administered to breastfeeding women.

Storage

Store in a cool, dry place away from direct sunlight. Keep containers tightly closed when not in use.

Indications

• Used as an excipient in tablet formulations
• Used as a bulking agent in capsule formulations
• Used in food products as a thickener or stabilizer

Dosage

Children: Refer to specific product guidelines as dosage will depend on the formulation and the active ingredients.

Adults: Refer to specific product guidelines as dosage will depend on the formulation and the active ingredients.

Mechanism of action

Microcrystalline cellulose acts as a non-digestible filler that enhances the flow properties of powders during the manufacturing of tablets and capsules. It does not have a direct pharmacological action on the body but ensures that the active ingredients are effectively delivered to the patient.

Pharmacodynamics

As a non-active ingredient, microcrystalline cellulose does not exert pharmacodynamic effects typical of active pharmaceutical ingredients. Its primary role is to provide a stable and consistent matrix for the drug, facilitating the release of the active compound once ingested.

Pharmacokinetics

Microcrystalline cellulose is not absorbed in the gastrointestinal tract; it passes through the digestive system largely unchanged. It adds bulk to the stool, which may aid in promoting regular bowel movements. The substance is excreted in feces, where it contributes to dietary fiber intake.

Pregnancy

Data regarding the use of microcrystalline cellulose during pregnancy is limited. It is advisable to consult with healthcare professionals before use.

Breast-feeding

Microcrystalline cellulose is considered safe during breastfeeding, as it is not absorbed systemically.

Storage

Store in a cool, dry place away from direct sunlight and moisture.

Indications

• Used as an emulsifying agent in pharmaceutical formulations
• Used in food products for texture and stability
• May be indicated in topical preparations to enhance drug absorption

Dosage

Children: Refer to specific product guidelines as doses can vary widely based on formulation and intended use.

Adults: Refer to specific product guidelines as doses can vary widely based on formulation and intended use.

Mechanism of action

Monostearate functions primarily as a surfactant. It reduces the surface tension between components in a mixture, allowing for better emulsification of oils and water. This action enhances the dispersion of active ingredients and improves their absorption in the gastrointestinal tract.

Pharmacodynamics

As an emulsifier, monostearate facilitates the formation of stable emulsions, which can lead to improved drug delivery and absorption. Its ability to enhance solubility of lipophilic compounds can result in increased bioavailability of certain drugs, making them more effective.

Pharmacokinetics

Monostearate is generally considered non-toxic and is metabolized by the body through hydrolysis into glycerol and stearic acid. It is poorly absorbed in the gastrointestinal tract due to its large molecular structure, and any absorbed amounts may be further metabolized or excreted. The onset and duration of action depend on the formulation in which it is used.

Pregnancy

Monostearate is generally considered safe for use during pregnancy, but it is important to consult with a healthcare provider for personalized advice.

Breast-feeding

Monostearate is typically regarded as safe during breastfeeding, but a healthcare provider should be consulted to ensure no adverse effects on the infant.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Monostearate powder
• Monostearate capsules
• Monostearate ointment

Indications

• Tablet coating
• Granule coating
• Improvement of drug stability
• Taste masking
• Aesthetic enhancement of pharmaceuticals

Dosage

Children: Dosage will depend on the specific formulation and active ingredients of the medication being coated. Refer to the specific product information for guidance.

Adults: Dosage will depend on the specific formulation and active ingredients of the medication being coated. Refer to the specific product information for guidance.

Mechanism of action

Opadry functions primarily as a coating polymer that adheres to the surface of tablets or granules, creating a protective layer. This layer can control the release of the active ingredient and protect it from environmental factors such as moisture and light. The specific composition of Opadry can vary, but it typically includes film-forming agents, plasticizers, and colorants that work together to achieve the desired coating characteristics.

Pharmacodynamics

The pharmacodynamics of Opadry is largely focused on its physical and chemical properties rather than specific biological interactions. The coating alters the dissolution characteristics of the drug, potentially leading to modified release profiles. This can enhance drug bioavailability or control the release rate of the active ingredient, thereby impacting the therapeutic effect.

Pharmacokinetics

As a coating agent, Opadry itself is not absorbed into the systemic circulation and does not have pharmacokinetic properties related to absorption, distribution, metabolism, or excretion of an active pharmaceutical ingredient. Its impact on pharmacokinetics is indirect, as it affects how the active drug is released and absorbed in the gastrointestinal tract.

Pregnancy

Opadry is a film-coating agent, and specific studies on its effects during pregnancy are not well-documented. Generally, it is advisable to use medications cautiously during pregnancy. Consult a healthcare provider for guidance.

Breast-feeding

Limited data are available regarding the safety of Opadry during breastfeeding. It is recommended to consult a healthcare provider before use.

Storage

Store in a cool, dry place away from direct sunlight and moisture. Keep out of reach of children.

Formulations

• Opadry OY - a coating system for oral solid dosage forms
• Opadry II - a polymer-based coating system for tablet and capsule applications

Indications

• Hormone replacement therapy
• Pain management
• Chronic disease management
• Certain psychiatric conditions
• Hormonal imbalance

Dosage

Children: Refer to specific product information and guidelines, as dosing will vary based on the active ingredient and clinical indication.

Adults: Refer to specific product information and guidelines, as dosing will vary based on the active ingredient and clinical indication.

Mechanism of action

Pellets can contain various active pharmaceutical ingredients that may act through different mechanisms. For example, hormone pellets release hormones such as testosterone or estrogen into the bloodstream, where they bind to specific receptors to exert their physiological effects. The controlled release mechanism allows for a gradual increase in hormone levels, mimicking the body's natural secretion patterns.

Pharmacodynamics

The pharmacodynamic effects of pellets depend on the active ingredients contained within them. For hormone pellets, the effects can include modulation of reproductive processes, alleviation of menopausal symptoms, or enhancement of muscle mass and strength in the case of testosterone. The controlled release mechanism helps maintain therapeutic levels of the drug in the plasma, which can lead to more stable and effective treatment outcomes.

Pharmacokinetics

The pharmacokinetics of pellets vary based on the specific drug formulation. Generally, after administration, pellets dissolve or disintegrate, allowing the active ingredient to be absorbed into the bloodstream. The rate of absorption and the time to peak plasma concentration will depend on the pellet's composition, the solubility of the drug, and the physiological conditions of the gastrointestinal tract or the application site. The half-life of the drug will also influence the dosing schedule and the duration of action.

Pregnancy

Safety in pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether this drug is excreted in human milk. Caution is advised when administering to nursing mothers.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Mechanism of action

The exact mechanism of action for Pink is not detailed in the provided information. However, compounds with similar structures often function as antagonists or inhibitors at certain receptors or enzymes, which modulates physiological processes.

Pharmacodynamics

Pharmacodynamics details for Pink are not specified. Typically, the pharmacodynamics of similar compounds involve interactions with neurotransmitter systems, influencing both central and peripheral nervous system functions. This can lead to varying therapeutic effects depending on the target receptors.

Pharmacokinetics

The pharmacokinetics of Pink, including absorption, distribution, metabolism, and excretion, are not explicitly stated. However, compounds of this nature generally exhibit moderate to high oral bioavailability, with metabolism primarily occurring in the liver, followed by renal excretion of metabolites.

Indications

• Emulsifying agent in drug formulations
• Stabilizer for parenteral preparations
• Solubilizer for hydrophobic drug compounds
• Ingredient in topical formulations

Dosage

Children: Refer to specific product guidelines, as dosing varies based on formulation and intended use.

Adults: Refer to specific product guidelines, as dosing varies based on formulation and intended use.

Mechanism of action

Polysorbate functions primarily as an emulsifying agent. It reduces the surface tension between immiscible liquids, allowing them to mix more easily. This property is particularly useful in stabilizing emulsions and suspensions, facilitating the delivery of active pharmaceutical ingredients in various formulations.

Pharmacodynamics

Polysorbate does not exert pharmacological effects in the traditional sense, as it does not bind to specific receptors to elicit a physiological response. Instead, it plays a crucial role in modifying the physical properties of drug formulations, thereby enhancing drug delivery and absorption. Its ability to solubilize drugs enhances their bioavailability, particularly for poorly soluble compounds.

Pharmacokinetics

Polysorbate is generally considered to be non-toxic and is not absorbed to a significant extent when administered orally. It is metabolized by the liver and excreted primarily through the gastrointestinal tract. The pharmacokinetic profile may vary depending on the route of administration and the specific formulation in which it is used.

Adverse effects

• Allergic reactions
• Skin irritation
• Gastrointestinal disturbances

Precautions

• Use cautiously in patients with known allergies to polysorbates or related compounds
• Monitor for allergic reactions in susceptible individuals

Pregnancy

Polysorbate is generally considered safe for use during pregnancy, but consult with a healthcare provider for specific cases.

Breast-feeding

Polysorbate is considered safe during breastfeeding, but consult with a healthcare provider for individual advice.

Storage

Store at room temperature, away from direct sunlight and moisture.

Formulations

• Polysorbate 20
• Polysorbate 80

Indications

• Topical antiseptic for skin disinfection
• Surgical scrubs and hand sanitizers
• Wound care management
• Pharmaceutical excipient in solid and liquid formulations

Dosage

Children: Refer to specific product guidelines for pediatric dosing recommendations, as doses can vary based on formulation and intended use.

Adults: Refer to specific product guidelines for dosing recommendations, as doses can vary based on the formulation and intended use.

Mechanism of action

Povidone acts by forming a complex with iodine when used as an antiseptic, which releases iodine slowly to exert its antimicrobial effect. The iodine disrupts microbial cell walls and interferes with protein synthesis, leading to cell death. Additionally, as a polymer, povidone can enhance drug solubility and stability by forming a hydrophilic matrix.

Pharmacodynamics

Povidone has a broad spectrum of antimicrobial activity against bacteria, viruses, and fungi. Its antiseptic properties are primarily due to the release of iodine, which is effective in reducing microbial load and preventing infection. The polymer's ability to bind to various substances allows it to be utilized in formulations that require improved stability and solubility.

Pharmacokinetics

Povidone is not absorbed systemically when applied topically, as it remains localized at the site of application. Its pharmacokinetics are largely dependent on the formulation and route of administration, with the polymer being metabolized by hydrolysis and excreted in urine as low-molecular-weight compounds. The release and activity of iodine are influenced by the concentration of povidone and the presence of organic matter.

Adverse effects

• Local irritation
• Allergic reactions
• Skin rashes
• Hypersensitivity reactions

Precautions

• Use with caution in patients with known allergies to iodine or povidone-iodine
• Avoid use in deep puncture wounds or serious burns

Pregnancy

Povidone is generally considered safe for use during pregnancy, but it is advisable to consult a healthcare professional before use.

Breast-feeding

Povidone is considered safe during breastfeeding, but it is recommended to consult a healthcare professional.

Storage

Store at room temperature, away from moisture and heat. Keep the container tightly closed.

Formulations

• Topical solution
• Ointment
• Surgical scrub
• Gauze impregnated with povidone-iodine

Dosage

Children: Refer to specific drug formulations and product labels as purified substances can vary widely in their use and dosing.

Adults: Refer to specific drug formulations and product labels as purified substances can vary widely in their use and dosing.

Mechanism of action

The mechanism of action for purified compounds varies widely depending on the specific substance. Generally, purified drugs exert their effects by interacting with specific biological targets, such as receptors, enzymes, or ion channels, leading to a desired therapeutic effect. This interaction can involve binding to receptors to activate or inhibit signaling pathways, modulating enzymatic activity, or altering physiological processes.

Pharmacodynamics

Pharmacodynamics describes the effects of a drug on the body and the relationship between drug concentration and effect. For purified drugs, this can involve dose-response relationships and the time course of their action. The purified form often enhances potency and reduces variability in response among patients, which can lead to more predictable therapeutic outcomes. The overall effect is determined by the drug's affinity for its target, the efficacy of the drug-receptor interaction, and the downstream signaling pathways activated as a result of this interaction.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion (ADME) of a drug. For purified substances, absorption can be more efficient due to the absence of impurities that may affect solubility or stability. Distribution may also be enhanced, leading to higher bioavailability. Metabolism can be influenced by the structure of the purified compound, as it may be metabolized more readily by liver enzymes. Excretion typically occurs through the kidneys or liver, depending on the molecular characteristics of the purified drug.

Pregnancy

Consult with a healthcare professional, as the safety of purified forms of medications during pregnancy may vary depending on the specific substance.

Breast-feeding

Consult with a healthcare professional, as the safety of purified forms of medications during breastfeeding may vary depending on the specific substance.

Storage

Store in a cool, dry place, away from light and moisture, and keep out of reach of children.

Dosage

Children: Refer to relevant clinical guidelines or consult a healthcare professional for dosing information.

Adults: Refer to relevant clinical guidelines or consult a healthcare professional for dosing information.

Pregnancy

Not enough data to determine safety. Consult healthcare provider.

Breast-feeding

Consult healthcare provider before use, as safety is not established.

Storage

Store in a cool, dry place away from direct sunlight.

Indications

• Silicosis
• Chronic obstructive pulmonary disease (COPD)
• Lung cancer associated with silica exposure

Dosage

Adults: Silica is not administered as a drug, but rather

Mechanism of action

Silica, particularly crystalline forms like quartz and cristobalite, can induce cytotoxicity and morphological transformation in cells. The cytotoxic effects are attributed to the presence of silanol groups and trace iron on the silica surface, which can generate reactive oxygen species. These interactions lead to cellular damage and transformation, suggesting multiple molecular mechanisms underlying silica's biological effects. The activity is sensitive to the silica's surface structure and composition, indicating that the biological response is a phenomenon originating from the silica's surface characteristics.

Pharmacodynamics

Silica's pharmacodynamic effects are largely related to its cytotoxic and transforming properties, particularly in lung tissue. The inhalation of crystalline silica can lead to the activation of inflammatory pathways, oxidative stress, and apoptosis in alveolar macrophages and epithelial cells. This can result in chronic inflammation, fibrosis, and ultimately, diseases such as silicosis and lung cancer. The degree of these effects varies based on the type of silica, its crystalline structure, and the presence of surface modifications.

Pharmacokinetics

The pharmacokinetics of silica is complex as it is not absorbed systemically when inhaled or ingested. Instead, inhaled silica particles can deposit in the alveolar region of the lungs, where they may persist for long periods. The body responds to silica exposure through inflammatory processes, and macrophages attempt to phagocytize silica particles. However, the persistence of these particles can lead to chronic lung conditions. Clearance mechanisms are inefficient, leading to prolonged retention in lung tissue.

Adverse effects

• Cytotoxicity
• Morphological transformation of cells
• Respiratory issues
• Silicosis
• Lung cancer

Precautions

• Use caution in occupational settings with silica dust exposure
• Regular monitoring of lung function in exposed individuals

Pregnancy

There is insufficient data on the effects of silica on pregnancy. It is advised to minimize exposure.

Breast-feeding

Limited data available; caution is advised due to potential respiratory effects.

Storage

Store in a cool, dry place, away from moisture and incompatible materials.

Formulations

• Crystalline silica
• Amorphous silica (diatomaceous earth)
• Silica gel

Indications

• Improvement of flow properties in powder formulations
• Preventing clumping in solid dosage forms
• Management of gastrointestinal disorders

Dosage

Children: Refer to specific formulation guidelines as silicified silica is typically used as an excipient and does not have a defined dosage.

Adults: Refer to specific formulation guidelines as silicified silica is typically used as an excipient and does not have a defined dosage.

Mechanism of action

Silicified silica acts by adsorbing moisture and preventing the clumping of powders. It also has the ability to absorb excess gastric acid, which can aid in the management of certain gastrointestinal conditions.

Pharmacodynamics

Silicified silica does not exert a direct pharmacological effect on body systems but improves the physical properties of pharmaceutical formulations. By promoting better flow and preventing caking, it enhances the bioavailability of active pharmaceutical ingredients (APIs).

Pharmacokinetics

Silica is not absorbed in the gastrointestinal tract and is excreted unchanged. Its pharmacokinetic profile is characterized by its inert nature and lack of systemic absorption, which allows it to function primarily at the site of administration.

Pregnancy

There is limited data on the use of silicified in pregnancy. Consult a healthcare provider before use.

Breast-feeding

It is unknown whether silicified is excreted in human milk. Caution is advised when administering to breastfeeding mothers.

Storage

Store in a tightly closed container, protected from moisture and light.

Indications

• Controlled drug delivery
• Targeted therapy
• Improvement of bioavailability of poorly soluble drugs

Dosage

Children: For pediatric dosing information, refer to guidelines specific to the drug being administered.

Adults: Dosage should be individualized based on the specific drug being delivered and the therapeutic goals. Refer to specific drug guidelines for accurate dosing information.

Mechanism of action

The mechanism of action of spheres primarily involves the encapsulation of active pharmaceutical ingredients (APIs) within a spherical matrix. Upon administration, the spheres can release the drug through diffusion, degradation of the matrix, or a combination of both processes. This allows for sustained or targeted delivery of the drug to specific sites within the body, improving treatment efficacy.

Pharmacodynamics

The pharmacodynamic properties of spheres depend on the drug they encapsulate and the design of the delivery system. Generally, spheres can enhance drug solubility and stability, allowing for improved bioavailability. The release profile can be tailored to achieve desired therapeutic concentrations over time, which can lead to improved patient adherence and reduced toxicity.

Pharmacokinetics

Pharmacokinetics of spheres is influenced by factors such as the size of the spheres, the material used for their construction, and the method of drug release. After administration, the spheres can be distributed through the bloodstream, and their release rates can vary based on their composition and the physiological conditions of the body. The elimination of the spheres and the encapsulated drug typically occurs via metabolic pathways and renal or hepatic clearance.

Pregnancy

Safety during pregnancy has not been established. Use only if potential benefits justify the risks to the fetus.

Breast-feeding

It is unknown whether spheres are excreted in human milk. Caution should be exercised when administered to a nursing woman.

Storage

Store in a cool, dry place away from direct sunlight and moisture.

Indications

• Dry skin conditions
• Cosmetic formulations
• Emollient in topical creams and lotions
• Emulsifying agent in pharmaceutical preparations

Dosage

Children: For pediatric use, refer to specific product formulations and guidelines, as dosing may vary based on the formulation and concentration.

Adults: Stearyl alcohol is used topically in various formulations. Specific dosing is typically determined by the formulation and intended use, refer to product guidelines for detailed instructions.

Mechanism of action

Stearyl alcohol functions primarily as an emollient and emulsifier. It aids in the formation of stable emulsions by reducing the surface tension between oil and water phases, allowing for the creation of creams and lotions. Its hydrophobic tail interacts with lipids, while the hydroxyl group can form hydrogen bonds with water, enhancing moisture retention in the skin.

Pharmacodynamics

Stearyl alcohol acts by providing a protective barrier on the skin, reducing transepidermal water loss and enhancing hydration. Its emollient properties make it effective in softening and smoothing the skin, which can alleviate dryness and improve the overall appearance of the skin. Additionally, it can enhance the delivery of other active ingredients in topical formulations.

Pharmacokinetics

Stearyl alcohol is not significantly absorbed systemically when applied topically. Its primary action is local to the site of application, where it exerts its emollient effects. The compound is metabolized in the body to various fatty acids and alcohols, and it is excreted primarily through the skin and gastrointestinal tract, with minimal systemic exposure.

Pregnancy

Stearyl is generally considered safe for use during pregnancy; however, specific formulations should be evaluated for their ingredients.

Breast-feeding

Stearyl can be used while breastfeeding, but it's recommended to consult a healthcare provider for specific concerns regarding topical applications.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Cream
• Ointment
• Lotion

Indications

• Providing energy in dietary supplementation
• Enhancing flavor in food products
• Replacement of carbohydrates in certain medical nutrition therapies

Dosage

Children: Refer to general dietary guidelines for carbohydrate intake in children. No specific dosing guidelines provided.

Adults: Refer to general dietary guidelines for carbohydrate intake. No specific dosing guidelines provided.

Mechanism of action

Sugar is metabolized in the body to provide energy. Upon ingestion, sucrose is broken down by the enzyme sucrase into its constituent monosaccharides, glucose and fructose, which are then absorbed into the bloodstream. These monosaccharides can be utilized by cells for energy or stored as glycogen in the liver and muscles.

Pharmacodynamics

As a simple carbohydrate, sugar elevates blood glucose levels rapidly after consumption, leading to increased insulin secretion from the pancreas. This insulin facilitates the uptake of glucose by tissues, promoting energy production. The rapid increase in blood sugar can provide quick energy but may also lead to potential negative effects on metabolism and weight if consumed in excess.

Pharmacokinetics

After oral administration, sugar is quickly hydrolyzed in the gastrointestinal tract. Peak plasma glucose concentrations typically occur within 30 minutes to 2 hours post-ingestion, depending on the amount consumed and individual metabolism. The half-life of glucose in the bloodstream is relatively short, as it is rapidly taken up by tissues or converted into glycogen.

Pregnancy

Sugar is generally considered safe for use during pregnancy, but excessive intake should be avoided to prevent gestational diabetes and excessive weight gain.

Breast-feeding

Sugar is safe during breastfeeding; however, excessive consumption should be avoided.

Storage

Store in a cool, dry place, away from moisture and direct sunlight.

Formulations

• Granulated sugar
• Brown sugar
• Powdered sugar
• Liquid sugar

Indications

• Used as an excipient in drug formulations
• Pleurodesis for the management of recurrent pleural effusions

Dosage

Children: Refer to specific guidelines for paediatric use, as dosing may differ based on age and clinical condition.

Adults: Refer to specific guidelines for the appropriate dosage in pleurodesis and other applications, as it may vary based on clinical context.

Mechanism of action

Talc exhibits very good absorptive properties, allowing it to absorb moisture and other substances effectively. This characteristic is particularly useful in pharmaceutical formulations, where it may enhance the stability and texture of the drug product.

Pharmacodynamics

Talc's primary pharmacodynamic effect is its ability to act as an inert filler and bulking agent in pharmaceutical preparations. It does not have any intrinsic pharmacological activity but serves to improve the physical properties of formulations, such as flowability and compressibility.

Pharmacokinetics

Talc is not absorbed systemically when used as an excipient or in medical procedures. Its effects are local, and it remains in the site of application, where it functions primarily as a mechanical agent. The pharmacokinetics of talc in the context of its use in pleurodesis involves its ability to promote adhesion of the pleural surfaces, thereby preventing fluid accumulation.

Pregnancy

Talc is classified as a substance with minimal systemic absorption, but safety during pregnancy has not been well established. Consult relevant guidelines.

Breast-feeding

Talc is not expected to be absorbed in significant amounts; however, caution is advised and consult guidelines.

Storage

Store in a cool, dry place, away from direct sunlight.

Dosage

Children: Refer to specific guidelines or pharmacological texts, as no established clinical dosing is available.

Adults: Refer to specific guidelines or pharmacological texts, as no established clinical dosing is available.

Mechanism of action

Triethyl functions as an alkylating agent, introducing alkyl groups into various substrates, which can lead to the modification of nucleic acids and proteins. This mechanism can result in the disruption of normal cellular processes, including inhibition of DNA replication and transcription, ultimately leading to cell death in susceptible cells. Its reactivity is primarily due to the presence of multiple ethyl groups, which can interact with nucleophilic sites in biological molecules.

Pharmacodynamics

The pharmacodynamics of triethyl are characterized by its ability to form covalent bonds with nucleophilic sites in biomolecules, influencing cellular functions and integrity. The modulation of DNA and protein function can lead to cytotoxic effects, particularly in rapidly dividing cells. Its effects may be dose-dependent, with higher concentrations resulting in increased toxicity and potential side effects.

Pharmacokinetics

Triethyl's pharmacokinetics are not well-studied in a clinical context, as it is primarily utilized in chemical processing rather than therapeutic applications. However, when considering alkylating agents in general, they may exhibit variable absorption, distribution, metabolism, and excretion depending on their chemical structure and the route of exposure. Following administration, such compounds can accumulate in tissues, particularly in the liver and kidneys, and may undergo metabolic transformation before excretion. Due to its reactive nature, triethyl can also pose risks of toxicity and adverse effects.

Adverse effects

• Nausea
• Vomiting
• Dizziness
• Headache
• Respiratory depression

Precautions

• Use with caution in patients with a history of respiratory issues
• Monitor liver function tests due to potential hepatotoxicity

Pregnancy

Triethyl is not recommended during pregnancy due to potential risks to the fetus.

Breast-feeding

Caution is advised as it is not known if triethyl is excreted in breast milk.

Storage

Store in a cool, dry place away from light and moisture.

Mechanism of action

Ethanol affects the brain’s neurons in several ways. It alters their membranes as well as their ion channels, enzymes, and receptors. Alcohol also binds directly to the receptors for acetylcholine, serotonin, GABA, and the NMDA receptors for glutamate. The sedative effects of ethanol are mediated through binding to GABA receptors and glycine receptors (alpha 1 and alpha 2 subunits). It also inhibits NMDA receptor functioning. In its role as an anti-infective, ethanol acts as an osmolyte or dehydrating agent that disrupts the osmotic balance across cell membranes. ... Ethanol is known to affect a large number of membrane proteins that participate in signaling pathways such as neurotransmitter receptors, enzymes, and ion channels, and there is extensive evidence that ethanol interacts with a variety of neurotransmitters. The major actions of ethanol involve enhancing the inhibitory effects of gamma-aminobutyric acid (GABA) at GABAa receptors and blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate, an excitatory amine acid (EAA) receptor. Animal studies indicate that the acute effects of ethanol result from competitive inhibition of glycine binding to NMDA receptor and disruption of glutamatergic neurotransmission by inhibiting the response of the NMDA receptor. Persistent glycine antagonism and attenuation of glutamatergic neurotransmission by chronic ethanol exposure results in tolerance to ethanol by enhancing EAA neurotransmission and NMDA receptor upregulation. The latter appears to involve selective increases in NMDA R2B subunit concentrations and other molecular changes in specific brain loci. The abrupt withdrawal of ethanol thus produces a hyperexcitable state that leads to the ethanol withdrawal syndrome and excitotoxic neuronal death. GABA-mediated inhibition, which normally acts to limit excitation, is eliminated during ethanol withdrawal syndrome and further intensifies this excitation. In addition, NMDA receptors function to inhibit the release of dopamine in the nucleus accumbens and mesolimbic structures, which modulate the reinforcing action of addictive xenobiotics such as ethanol. By inhibiting NMDA receptor activity, ethanol could increase dopamine release from the nucleus accumbens and ventral tegmental area and could thus create dependence. Chronic ethanol administration also results in tolerance, dependence, and an ethanol withdrawal syndrome, mediated, in part, by desensitization and or downregulation of GABAa receptors. The development of alcoholic ketoacidosis (AKA) requires that a combination of physical and physiologic events occur. The normal response to starvation and depletion of hepatic glycogen stores is for amino acids to be converted to pyruvate. Pyruvate can serve as a substrate for gluconeogenesis, be converted to acetyl-CoA, which can enter the Krebs cycle or can be utilized in various biosynthetic pathways (eg, fatty acid, ketone bodies, cholesterol, and acetylcholine) ... Ethanol metabolism generates NADH, resulting in an excess of reducing potential. This high redox state favors the conversion of pyruvate to lactate, diverting pyruvate from being a substrate for gluconeogenesis. To compensate for the lack of normal metabolic substrates, the body mobilizes fat from adipose tissue and increased fatty acid metabolism as an alternative source of energy. This response is mediated by a decrease in insulin and an increased secretion of glucagon, catecholamines, growth hormone, and cortisol. Fatty acid metabolism results in the formation of acetyl-CoA and it combines with the excess acetate that is generated from ethanol metabolism to form acetoacetate. Most of the acetoacetate is reduced to beta-hydroxybutyrate due to the excess reducing potential or high redox state of the cell. Volume depletion interferes with the renal elimination of acetoacetate and beta-hydroxybutyrate, and contributes to the acidosis. An elevated lactate concentration may result from shunting from pyruvate or

Pharmacodynamics

Alcohol produces injury to cells by dehydration and precipitation of the cytoplasm or protoplasm. This accounts for its bacteriocidal and antifungal action. When alcohol is injected in close proximity to nerve tissues, it produces neuritis and nerve degeneration (neurolysis). Ninety to 98% of ethanol that enters the body is completely oxidized. Ethanol is also used as a cosolvent to dissolve many insoluble drugs and to serve as a mild sedative in some medicinal formulations. Ethanol also binds to GABA, glycine, NMDA receptors and modulates their effects. Ethanol is also metabolised by the hepatic enzyme alcohol dehydrogenase.

Mechanism of action

Esomeprazole exerts its stomach acid-suppressing effects by preventing the final step in gastric acid production by covalently binding to sulfhydryl groups of cysteines found on the (H+, K+)-ATPase enzyme at the secretory surface of gastric parietal cells. This effect leads to inhibition of both basal and stimulated gastric acid secretion, irrespective of the stimulus. As the binding of esomeprazole to the (H+, K+)-ATPase enzyme is irreversible and new enzyme needs to be expressed in order to resume acid secretion, esomeprazole's duration of antisecretory effect that persists longer than 24 hours. Esomeprazole is a proton pump inhibitor that suppresses gastric acid secretion by specific inhibition of the H+/K+-ATPase in the gastric parietal cell. The S- and R-isomers of omeprazole are protonated and converted in the acidic compartment of the parietal cell forming the active inhibitor, the achiral sulphenamide. By acting specifically on the proton pump, esomeprazole blocks the final step in acid production, thus reducing gastric acidity. This effect is dose-related up to a daily dose of 20 to 40 mg and leads to inhibition of gastric acid secretion.

Pharmacodynamics

Esomeprazole is a compound that inhibits gastric acid secretion and is indicated in the treatment of gastroesophageal reflux disease (GERD), the healing of erosive esophagitis, and <i>H. pylori</i> eradication to reduce the risk of duodenal ulcer recurrence. Esomeprazole belongs to a new class of antisecretory compounds, the substituted benzimidazoles, that do not exhibit anticholinergic or H2 histamine antagonistic properties, but that suppress gastric acid secretion by specific inhibition of the H⁺/K⁺ ATPase at the secretory surface of the gastric parietal cell. By doing so, it inhibits acid secretion into the gsatric lumen. This effect is dose-related and leads to inhibition of both basal and stimulated acid secretion irrespective of the stimulus. Esomeprazole is the s-isomer of [DB00338], which is a racemate of the S- and R-enantiomer. Esomeprazole has been shown to inhibit acid secretion to a similar extent as [DB00338], without any significant differences between the two compounds _in vitro_. PPIs such as esomeprazole have also been shown to inhibit the activity of dimethylarginine dimethylaminohydrolase (DDAH), an enzyme necessary for cardiovascular health. DDAH inhibition causes a consequent accumulation of the nitric oxide synthase inhibitor asymmetric dimethylarginie (ADMA), which is thought to cause the association of PPIs with increased risk of cardiovascular events in patients with unstable coronary syndromes. Due to their good safety profile and as several PPIs are available over the counter without a prescription, their current use in North America is widespread. Long term use of PPIs such as esomeprazole has been associated with possible adverse effects, however, including increased susceptibility to bacterial infections (including gastrointestinal _C. difficile_), reduced absorption of micronutrients including iron and B12, and an increased risk of developing hypomagnesemia and hypocalcemia which may contribute to osteoporosis and bone fractures later in life.

Mechanism of action

Ethanol affects the brain’s neurons in several ways. It alters their membranes as well as their ion channels, enzymes, and receptors. Alcohol also binds directly to the receptors for acetylcholine, serotonin, GABA, and the NMDA receptors for glutamate. The sedative effects of ethanol are mediated through binding to GABA receptors and glycine receptors (alpha 1 and alpha 2 subunits). It also inhibits NMDA receptor functioning. In its role as an anti-infective, ethanol acts as an osmolyte or dehydrating agent that disrupts the osmotic balance across cell membranes. ... Ethanol is known to affect a large number of membrane proteins that participate in signaling pathways such as neurotransmitter receptors, enzymes, and ion channels, and there is extensive evidence that ethanol interacts with a variety of neurotransmitters. The major actions of ethanol involve enhancing the inhibitory effects of gamma-aminobutyric acid (GABA) at GABAa receptors and blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate, an excitatory amine acid (EAA) receptor. Animal studies indicate that the acute effects of ethanol result from competitive inhibition of glycine binding to NMDA receptor and disruption of glutamatergic neurotransmission by inhibiting the response of the NMDA receptor. Persistent glycine antagonism and attenuation of glutamatergic neurotransmission by chronic ethanol exposure results in tolerance to ethanol by enhancing EAA neurotransmission and NMDA receptor upregulation. The latter appears to involve selective increases in NMDA R2B subunit concentrations and other molecular changes in specific brain loci. The abrupt withdrawal of ethanol thus produces a hyperexcitable state that leads to the ethanol withdrawal syndrome and excitotoxic neuronal death. GABA-mediated inhibition, which normally acts to limit excitation, is eliminated during ethanol withdrawal syndrome and further intensifies this excitation. In addition, NMDA receptors function to inhibit the release of dopamine in the nucleus accumbens and mesolimbic structures, which modulate the reinforcing action of addictive xenobiotics such as ethanol. By inhibiting NMDA receptor activity, ethanol could increase dopamine release from the nucleus accumbens and ventral tegmental area and could thus create dependence. Chronic ethanol administration also results in tolerance, dependence, and an ethanol withdrawal syndrome, mediated, in part, by desensitization and or downregulation of GABAa receptors. The development of alcoholic ketoacidosis (AKA) requires that a combination of physical and physiologic events occur. The normal response to starvation and depletion of hepatic glycogen stores is for amino acids to be converted to pyruvate. Pyruvate can serve as a substrate for gluconeogenesis, be converted to acetyl-CoA, which can enter the Krebs cycle or can be utilized in various biosynthetic pathways (eg, fatty acid, ketone bodies, cholesterol, and acetylcholine) ... Ethanol metabolism generates NADH, resulting in an excess of reducing potential. This high redox state favors the conversion of pyruvate to lactate, diverting pyruvate from being a substrate for gluconeogenesis. To compensate for the lack of normal metabolic substrates, the body mobilizes fat from adipose tissue and increased fatty acid metabolism as an alternative source of energy. This response is mediated by a decrease in insulin and an increased secretion of glucagon, catecholamines, growth hormone, and cortisol. Fatty acid metabolism results in the formation of acetyl-CoA and it combines with the excess acetate that is generated from ethanol metabolism to form acetoacetate. Most of the acetoacetate is reduced to beta-hydroxybutyrate due to the excess reducing potential or high redox state of the cell. Volume depletion interferes with the renal elimination of acetoacetate and beta-hydroxybutyrate, and contributes to the acidosis. An elevated lactate concentration may result from shunting from pyruvate or

Pharmacodynamics

Alcohol produces injury to cells by dehydration and precipitation of the cytoplasm or protoplasm. This accounts for its bacteriocidal and antifungal action. When alcohol is injected in close proximity to nerve tissues, it produces neuritis and nerve degeneration (neurolysis). Ninety to 98% of ethanol that enters the body is completely oxidized. Ethanol is also used as a cosolvent to dissolve many insoluble drugs and to serve as a mild sedative in some medicinal formulations. Ethanol also binds to GABA, glycine, NMDA receptors and modulates their effects. Ethanol is also metabolised by the hepatic enzyme alcohol dehydrogenase.

Mechanism of action

Nitroglycerin is converted by mitochondrial aldehyde dehydrogenase in smooth muscle cells to nitric oxide (NO), a potent vasodilator. NO activates the enzyme guanylate cyclase, which converts guanosine triphosphate (GTP) to cyclic guanosine 3',5'-monophosphate (cGMP) in vascular smooth muscle and other tissues. cGMP is an endogenous vasodilator of vascular smooth muscle: it causes protein kinase-dependent phosphorylation and activates downstream cascades that promote relaxation and increased blood flow in veins, arteries and cardiac tissue. An _in vitro_ study using mouse aorta suggests that nitric oxide, an active metabolite of nitroglycerin, targets the natriuretic peptide receptors. The drugs used to treat angina alleviate symptoms by increasing blood flow to the ischemic myocardium and/or by reducing myocardial oxygen requirements. ... /Nitrates/ reduce myocardial oxygen requirements through their effects on the systemic circulation. Their major systemic action is a reduction in venous tone, which leads to pooling of blood in peripheral veins, decreased venous return, and reduced ventricular volume and myocardial tension (preload). /Org nitrates/ Although it predominately affects vascular smooth muscle /nitroglycerin/, the bronchioles, gastrointestinal tract (including biliary system), ureters, and uterus are affected. Free radicals of nitric oxide may activate guanylate cyclase, resulting in increased synthesis of cyclic GMP. Nitric oxide may combine with sulfhydryl groups in the endothelium and produce S-nitrosothiols, which stimulate guanylate cyclase production. N-acetyl-cycteine may enhance this process by providing a source of sulfhydryl groups. Cyclic GMP appears to reduce stored calcium and interfere with calcium-activated smooth muscle contractions. Organic nitrates... lead to the formation of the reactive free radical nitric oxide, which can activate guanylyl cyclase and increase the synthesis of cyclic GMP in smooth muscle and other tissues... A cyclic GMP-dependent protein kinase catalyzes the phosphorylation of various proteins in smooth muscle. Eventually, the light chain of myosin is dephosphorylated. Phosphorylation of the myosin chain regulates the maintenance of the contractile state in smooth muscle. Nitrates also may alter the prostaglandin system by inhibiting thromboxane synthetase and permitting preferential formation of prostacyclin over thromboxane A2. Both of these two short-acting vasoactive substances are formed from prostaglandin precursors. Prostacyclin is a potent vasodilator which causes smooth muscle relaxation through phosphorylation of the myosin light chain kinase. This reduces its ability to to be activated by calciun and calmodulin.

Pharmacodynamics

Nitroglycerin causes the relaxation of vascular smooth muscles, causing arteriolar and venous dilatation. It increases blood flow to the myocardium and reduces cardiac preload and afterload, decreasing myocardial wall stress and ameliorating anginal symptoms. Nitroglycerin also reduces coronary artery spasm, decreasing systemic vascular resistance as well as systolic and diastolic blood pressure. Like other organic nitrates, repeated and prolonged administration of nitroglycerin can lead to the development of tolerance or desensitization of vascular smooth muscle to further nitroglycerin-induced vasorelaxation. This loss of efficacy may be associated with the inhibition of mitochondrial aldehyde dehydrogenase, which is an important enzyme involved in the bioactivation of nitroglycerin. Nitroglycerin tolerance may be accompanied by pro-oxidant effects, endothelial dysfunction, and increased sensitivity to vasoconstrictors.

Mechanism of action

...Some quartz and cristobalite dusts (crystalline) as well as the diatomaceous earths (amorphous), but not the pyrogenic amorphous silica, were cytotoxic and induced morphological transformation of SHE cells in a concentration-dependent manner. The ranking in cytotoxicity was different from that in transforming potency, suggesting two separate molecular mechanisms for the two effects. The cytotoxic and transforming potencies were different from one dust to another, even among the same structural silicas. The type of crystalline structure (quartz vs cristobalite) and the crystalline vs biogenic amorphous form did not correlate with cytotoxic or transforming potency of silica dusts. Comparison of cellular effects induced by original and surface modified samples revealed that several surface functionalities modulate cytotoxic and transforming potencies. The cytotoxic effects appeared to be related to the distribution and abundance of silanol groups and to the presence of trace amounts of iron on the silica surface. Silica particles with fractured surfaces and/or iron-active sites, able to generate reactive oxygen species, induced SHE cell transformation. The results show that the activity of silica at the cellular level is sensitive to the composition and structure of surface functionalities and confirm that the biological response to silica is a surface originated phenomenon. In vivo exposure of rat lungs to crystalline silica either by intratracheal instillation or by inhalation results in an increase in mRNA levels for inducible nitric oxide synthase (iNOS) in bronchoalveolar lavage cells (BALC), elevated nitric oxide (.NO) production by BALC, and an increase in .NO-dependent chemiluminescence (CL) from alveolar macrophages (AM). Induction of iNOS message occurs in both AM and polymorphonuclear leukocytes (PMN) harvested from silica-exposed lungs but is not significantly elevated in lavaged lung tissue. This review presents characteristics of simple and complicated coal workers' pneumoconiosis (CWP) as well as pathologic indices of acute and chronic silicosis by summarizing results of in vitro, animal, and human investigations. These results support four basic mechanisms in the etiology of CWP and silicosis: a) direct cytotoxicity of coal dust or silica, resulting in lung cell damage, release of lipases and proteases, and eventual lung scarring; b) activation of oxidant production by pulmonary phagocytes, which overwhelms the antioxidant defenses and leads to lipid peroxidation, protein nitrosation, cell injury, and lung scarring; c) activation of mediator release from alveolar macrophages and epithelial cells, which leads to recruitment of polymorphonuclear leukocytes and macrophages, resulting in the production of proinflammatory cytokines and reactive species and in further lung injury and scarring; d) secretion of growth factors from alveolar macrophages and epithelial cells, stimulating fibroblast proliferation and eventual scarring. Results of in vitro and animal studies provide a basis for proposing these mechanisms for the initiation and progression of pneumoconiosis. Data obtained from exposed workers lend support to these mechanisms. /The authors/ reported previously that freshly fractured silica (FFSi) induces activator protein-1 (AP-1) activation through extracellular signal-regulated protein kinases (ERKs) and p38 kinase pathways. In the present study, the biologic activities of FFSi and aged silica (ASi) were compared by measuring their effects on the AP-1 activation and phosphorylation of ERKs and p38 kinase. The roles of reactive oxygen species (ROS) in this silica-induced AP-1 activation were also investigated. FFSi-induced AP-1 activation was four times higher than that of ASi in JB6 cells. FFSi also caused greater phosphorylation of ERKs and p38 kinase than ASi. FFSi generated more ROS than ASi when incubated with the cells as measured by electron spin resonance (ESR). Studies using ROS-sensitive dyes and

Mechanism of action

It has very good absorptive properties.