Clarem

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

• Bacterial infections
• Community-acquired pneumonia
• Skin infections
• Prophylaxis for certain infections

Dosage

Adults: 500 mg once daily for

Mechanism of action

Clarithromycin is metabolized to 14-OH clarithromycin, which is active. It penetrates bacterial cell walls and reversibly binds to domain V of the 23S ribosomal RNA of the 50S ribosomal subunit, blocking the translocation of aminoacyl-tRNA and inhibiting polypeptide synthesis. It may be bactericidal in high concentrations against susceptible organisms, particularly Streptococcus pyogenes, S. pneumoniae, Haemophilus influenzae, and Chlamydia trachomatis. Additionally, clarithromycin inhibits the hepatic microsomal CYP3A4 isoenzyme and P-glycoprotein.

Pharmacodynamics

Clarithromycin exhibits a broad spectrum of activity against numerous gram-positive bacteria, including Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes. It also shows activity against gram-negative bacteria such as Haemophilus influenzae and Moraxella catarrhalis, as well as against various anaerobic bacteria, mycobacteria, and other organisms like Mycoplasma, Ureaplasma, and Chlamydia. While typically bacteriostatic, it can sometimes demonstrate bactericidal properties depending on the concentration and the organism.

Pharmacokinetics

Clarithromycin is well absorbed after oral administration, with its bioavailability enhanced by food. It is extensively metabolized in the liver, primarily via CYP3A4, leading to active metabolites. The drug has a half-life of approximately 3 to 4 hours, but its active metabolite, 14-OH clarithromycin, has a longer half-life, contributing to its prolonged activity. Renal impairment can significantly affect its clearance, necessitating dosage adjustments in patients with reduced renal function.

Adverse effects

• Nausea
• Diarrhea
• Abdominal pain
• Dysgeusia
• Headache
• Rash
• Liver enzyme elevations
• QT prolongation

Interactions

• Clarithromycin + acalabrutinib: Severe (increases exposure)
• Clarithromycin + antiarrhythmics: Severe (increases exposure)
• Clarithromycin + dronedarone: Severe (increases exposure)
• Clarithromycin + non-sedating antihistamines: Severe (increases exposure)
• Clarithromycin + mizolastine: Severe (increases exposure)
• Clarithromycin + lurasidone: Severe (increases exposure)
• Clarithromycin + quetiapine: Severe (increases exposure)
• Clarithromycin + avapritinib: Severe (increases exposure)
• Clarithromycin + benzodiazepines: Severe (increases exposure)
• Clarithromycin + alprazolam: Severe (increases exposure)

Precautions

• Caution in hepatic impairment
• Use with caution in renal impairment
• Monitor for signs of QT prolongation
• Consider alternative therapy in patients with history of arrhythmias
• Use with caution in patients with myasthenia gravis due to potential exacerbation

Pregnancy

Manufacturers advise use only if adequate alternatives are not available.

Breast-feeding

Present in milk; use only if no suitable alternatives.

Storage

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

Formulations

• Oral suspension 200 mg/5 mL
• Capsules 250 mg

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

• Monitoring respiratory function
• Assessment of metabolic status
• Management of respiratory acidosis
• Management of respiratory alkalosis

Dosage

Children: Dosing for interventions related to carbon dioxide levels in pediatric patients should be guided by clinical protocols and the BNF for Children.

Adults: Dosing for interventions related to carbon dioxide levels is typically based on clinical assessment and individual patient needs. Refer to clinical guidelines for specific scenarios.

Mechanism of action

Carbon dioxide acts primarily as a signaling molecule in the body, influencing respiratory drive and blood pH. It is produced during cellular respiration and is a critical component of the bicarbonate buffering system, which helps maintain acid-base homeostasis. Elevated levels of CO2 in the blood stimulate ventilation in the lungs, increasing the rate of gas exchange and facilitating the removal of excess CO2.

Pharmacodynamics

The pharmacodynamic effects of dioxides, particularly carbon dioxide, are closely related to its concentration in the blood. As CO2 levels increase, it leads to respiratory acidosis, which can stimulate the respiratory centers in the brain to increase ventilation. Conversely, low levels of CO2 can cause respiratory alkalosis, potentially leading to decreased respiratory drive. CO2 also plays a role in vasodilation and can affect blood flow and pressure through its influence on smooth muscle tone.

Pharmacokinetics

Carbon dioxide is produced endogenously during metabolic processes and is transported in the bloodstream primarily in three forms: dissolved in plasma, as bicarbonate ions (HCO3-), and bound to hemoglobin. The half-life of CO2 in the bloodstream is very short due to its rapid exchange with alveolar gas in the lungs. The elimination of CO2 occurs through exhalation, making it a dynamic component of respiratory physiology.

Pregnancy

Data on the effects of dioxide during pregnancy are limited. Caution is advised due to potential risks associated with exposure.

Breast-feeding

Limited data are available regarding the excretion of dioxide in human milk. Caution is recommended.

Storage

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

Indications

• Enhancement of taste in food and beverages
• Improvement of palatability in nutritional products
• Masking undesirable flavors in medications

Dosage

Children: There is no specific pediatric dosage for flavor agents as they are used as needed to improve the taste of food and beverages.

Adults: There is no specific dosage for flavor agents as they are used as needed to achieve the desired taste and aroma in food and beverages.

Mechanism of action

Flavor compounds interact with taste receptors on the tongue, stimulating the sensory neurons responsible for taste perception. This interaction influences the overall flavor profile of food and beverages, enhancing the eating experience. Some flavors may also have a psychological effect, stimulating appetite or evoking pleasant memories associated with certain tastes.

Pharmacodynamics

While flavor agents are primarily used for sensory enhancement in food, their pharmacodynamic effects are minimal as they are not designed to elicit a pharmacological response. However, certain flavors may influence digestion and metabolism indirectly by enhancing saliva production or affecting gut motility. The enjoyment of flavored products can also lead to increased food intake and satisfaction.

Pharmacokinetics

Flavour compounds are typically ingested and metabolized by the body. Their absorption rates can vary depending on their chemical structure and formulation. Once ingested, they may be rapidly metabolized in the liver and other tissues, with excretion primarily via urine. The specific pharmacokinetic profiles of flavor agents can vary significantly based on their source and chemical properties.

Pregnancy

Flavours are generally considered safe for use during pregnancy, but specific assessments should be made based on the type of flavouring agent.

Breast-feeding

Most flavouring agents are deemed safe during breastfeeding, although it's advisable to consult healthcare professionals regarding specific ingredients.

Storage

Store in a cool, dry place away from direct sunlight and heat sources. Ensure that the container is tightly sealed to prevent contamination.

Dosage

Children: Refer to specific clinical guidelines for dosing in children, as no standard paediatric dosage is specified in the provided resources.

Adults: Refer to specific clinical guidelines for dosing, as no standard adult dosage is specified in the provided resources.

Mechanism of action

Ethylene glycol toxicity results from its metabolism to glycolic acid and other toxic metabolites. Glycolate accumulates in the body and is eliminated more slowly than ethylene glycol itself. The renal excretion of both compounds plays a crucial role in their elimination, accounting for a significant portion of the administered dose.

Pharmacodynamics

The pharmacodynamics of glycolate are closely tied to its role as a metabolite of ethylene glycol. Its accumulation can lead to metabolic acidosis, although minimal clinical effects have been observed at low doses. The relationship between glycolate and ethylene glycol indicates that glycolate may contribute to the overall toxic effects of ethylene glycol ingestion.

Pharmacokinetics

The pharmacokinetics of glycolate indicate that it reaches peak plasma levels between 4-6 hours after the administration of ethylene glycol. The elimination half-life of ethylene glycol is approximately 1.7 hours in rats and 3.4 hours in dogs. Glycolate is predominantly eliminated through renal excretion, with about 5% of the dose being excreted unchanged.

Pregnancy

There is limited data on the safety of glycolate in pregnancy. Caution is advised.

Breast-feeding

Data on the excretion of glycolate in human milk is not available. Caution is advised.

Storage

Store at room temperature, away from light and moisture.

Indications

• Constipation
• Bowel preparation for diagnostic procedures (e.g., colonoscopy)

Dosage

Children: For children, macrogol is typically used at a dose of 0.5 to 1 g/kg per day, not exceeding 17 g per day, depending on the child's age and condition. Refer to the BNF for Children for detailed pediatric dosing guidance.

Adults: Typical adult dosing for constipation is 8.4 grams of macrogol powder dissolved in water, taken once daily. For bowel preparation, specific dosing regimens may vary, and it is essential to follow product instructions or medical advice.

Mechanism of action

Macrogol works as an osmotic agent, drawing water into the bowel lumen through osmosis. This increased water content softens the stool, making it easier to pass. The presence of macrogol in the intestine increases the volume and viscosity of the stool, stimulating peristalsis and facilitating bowel evacuation.

Pharmacodynamics

Macrogol's laxative effect is dose-dependent, with higher doses generally resulting in more significant bowel movement stimulation. It is not absorbed systemically, which minimizes potential side effects and interactions. The osmotic effect leads to an increase in intraluminal pressure and stool volume, contributing to effective evacuation.

Pharmacokinetics

Macrogol is largely non-absorbed in the gastrointestinal tract, which allows it to exert its effects locally within the bowel. Due to its high molecular weight, it remains in the intestinal lumen, where it facilitates water retention. Elimination occurs through feces, as it is not metabolized by the body.

Pregnancy

Macrogol can be used during pregnancy if necessary, but caution should be exercised and medical advice sought.

Breast-feeding

Macrogol is generally considered safe to use during breastfeeding.

Storage

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

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.

Dosage

Children: Refer to BNF for Children for specific recommendations regarding the consumption of orange juice in children.

Adults: There is no standard dosage for orange juice as it is typically consumed as a beverage. Moderation is advised, especially for individuals on certain medications.

Mechanism of action

The exact mechanism of action of orange juice is not fully understood, but it is known to contain compounds that can influence the metabolism of certain drugs. For instance, it may affect the activity of cytochrome P450 enzymes, particularly CYP3A4, which can alter the pharmacokinetics of medications.

Pharmacodynamics

Orange juice is known to enhance the bioavailability of certain nutrients and may influence the pharmacological effects of some drugs. Its high vitamin C content contributes to various physiological functions, including antioxidant activity, which may indirectly support overall health.

Pharmacokinetics

The pharmacokinetics of orange juice itself are not extensively studied, but it is generally absorbed well through the gastrointestinal tract. The compounds in orange juice can affect the absorption and metabolism of medications, leading to varied clinical effects depending on the drug in question.

Interactions

• orange juice + celiprolol: Unknown (decreases exposure)

Formulations

• juice
• whole fruit

Indications

• Preoperative skin antisepsis
• Wound irrigation and cleansing
• Management of minor cuts and abrasions
• Treatment of minor skin infections
• Disinfection of mucous membranes

Dosage

Children: Refer to specific product guidelines for concentration and application method, as doses may vary by formulation.

Adults: Refer to specific product guidelines for concentration and application method, as doses may vary by formulation.

Mechanism of action

Povidone-iodine exerts its antiseptic effects primarily through the release of free iodine, which penetrates microbial cell walls and disrupts protein and nucleic acid synthesis. This leads to cell lysis and death of a wide variety of pathogens. The mechanism involves the oxidation of essential cellular components, thus rendering microorganisms inactive.

Pharmacodynamics

Povidone-iodine demonstrates rapid bactericidal activity, effectively reducing the microbial load on the skin and in wounds. The antimicrobial efficacy is influenced by factors such as concentration, exposure time, and the presence of organic matter. Its broad-spectrum action makes it effective against gram-positive and gram-negative bacteria, fungi, and viruses, making it a versatile antiseptic.

Pharmacokinetics

Povidone-iodine is not significantly absorbed through intact skin; however, some absorption may occur with large or prolonged applications, especially on compromised skin. The elimination half-life of iodide is approximately 24 hours, with the majority excreted unchanged in the urine. Iodine levels can be temporarily elevated in the serum after application, particularly in patients with pre-existing thyroid conditions.

Contra-indications

• Hypersensitivity to povidone-iodine or any of the excipients
• Thyroid dysfunction
• Use in infants less than 2 months of age

Adverse effects

• Skin irritation
• Burning sensation
• Allergic reactions
• Staining of skin and clothing
• Thyroid dysfunction
• Electrolyte imbalance (with prolonged use)

Interactions

• May interfere with thyroid function tests
• Incompatibility with other antiseptics or disinfectants

Precautions

• Avoid contact with eyes
• Use with caution in patients with thyroid disease
• Not for deep puncture wounds or serious burns

Pregnancy

Generally considered safe for topical use, but should be used with caution. Consult a healthcare professional for guidance.

Breast-feeding

Suitable for topical use, but excessive use should be avoided. Consult a healthcare professional for guidance.

Storage

Store at room temperature, away from direct sunlight. Keep container tightly closed.

Formulations

• Topical solution
• Ointment
• Surgical scrub
• Swab sticks

Indications

• Used in agriculture to regulate plant growth
• Commonly applied to cereal crops to prevent lodging
• Enhances crop yield and stability

Mechanism of action

Chlormequat chloride acts at the nicotinic receptor site of the neuromuscular junction, functioning as a depolarizing agent. This action leads to initial muscular excitation which is then followed by muscle weakness. The acute toxicity of chlormequat chloride may result in respiratory arrest, and its effects can vary by species due to differing sensitivities to depolarizing neuromuscular blockers.

Pharmacodynamics

Chlormequat chloride inhibits gibberellin biosynthesis, a key hormone in plant growth regulation, which leads to reduced cell elongation and overall dwarfing of plants. This mechanism helps enhance crop stability and yield by minimizing the risk of lodging in cereals, thus promoting a more efficient harvest.

Pharmacokinetics

The pharmacokinetics of chlormequat chloride in plants involves absorption, translocation, and metabolism within plant tissues. It is rapidly absorbed and translocated throughout the plant, with a relatively short half-life, leading to effective growth regulation while minimizing residues in harvested products.

Pregnancy

No adequate and well-controlled studies in pregnant women have been conducted. Use only if clearly needed.

Breast-feeding

It is not known whether chlormequat chloride is excreted in human milk. Caution should be exercised when administering to a nursing mother.

Storage

Store in a cool, dry place. Keep container tightly closed.

Indications

• Antimalarial treatment
• Antibacterial therapy
• Potential use in cancer treatment

Dosage

Children: Refer to the BNF for Children for guidance on paediatric dosing, as it is crucial to adjust the dosage based on the child's weight and age.

Adults: Refer to the BNF for specific indications and dosing information for adults, as dosage can vary based on the condition being treated.

Mechanism of action

Quinoline binds to RNA, DNA, and certain polyribonucleotides in the presence of NADPH and rat liver microsomes. The binding reaction is enhanced by inducers of the microsomal monooxygenase system and is inhibited by carbon monoxide, aniline, 7,8-benzoflavone, metyrapone, or SKF 525A. Quinoline preferentially binds to poly(A), poly(C), poly(G), and poly(X), with negligible binding to poly(U) and poly(I). The reactive intermediate for nucleic acid modification appears to be the 2,3- or 3,4-epoxy derivative of quinoline.

Pharmacodynamics

Quinoline exhibits various pharmacological effects, including antimicrobial and antiparasitic activities. Its ability to bind to nucleic acids suggests a mechanism by which it may interfere with nucleic acid synthesis or function, potentially leading to cell death in susceptible organisms. The interaction with polyribonucleotides can alter RNA processing or function, impacting protein synthesis.

Pharmacokinetics

Information on the pharmacokinetics of quinoline is limited. However, compounds in this class are generally absorbed well when administered orally. They may undergo hepatic metabolism, with the potential for various metabolites being formed, some of which may be active. Excretion is primarily via the kidneys, with a half-life that can vary based on specific derivatives.

Pregnancy

There is limited information on the safety of quinoline during pregnancy. It is recommended to avoid use unless absolutely necessary.

Breast-feeding

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

Storage

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

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

• Nutritional supplementation
• Energy source in enteral nutrition
• Excipient in pharmaceutical formulations

Dosage

Children: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Adults: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Mechanism of action

Starch is broken down into glucose units by enzymes such as amylase during digestion. The glucose is then absorbed in the intestines and utilized for energy production in the body's cells. This pathway involves hydrolysis of the glycosidic bonds, converting starch into simpler sugars.

Pharmacodynamics

Starch primarily serves as an energy source. Its digestion and absorption lead to an increase in blood glucose levels, which provides energy for metabolic processes. In this context, it plays a crucial role in maintaining energy homeostasis in the body.

Pharmacokinetics

Starch is not absorbed in its polymeric form; it must first be enzymatically hydrolyzed into simpler sugars such as maltose and glucose. The digestion and absorption of starch occur predominantly in the small intestine, with glucose being readily absorbed into the bloodstream. The rate of absorption can vary depending on the type of starch and its physical form.

Adverse effects

• Allergic reactions
• Gastrointestinal discomfort
• Diarrhea
• Constipation

Precautions

• Use with caution in individuals with known allergies to starch or starch derivatives
• Monitor for gastrointestinal symptoms in patients with a history of digestive disorders

Pregnancy

Starch is generally considered safe for use during pregnancy. However, it should be consumed in moderation as part of a balanced diet.

Breast-feeding

Starch is deemed safe for nursing mothers when used in moderation as part of a balanced diet.

Storage

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

Formulations

• Powder
• Granules
• Tablets
• Suspensions

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.

Indications

• Orthopedic implants
• Dental implants
• Prosthetic devices
• Surgical instruments

Mechanism of action

Titanium does not have a specific mechanism of action as it is not a drug in the traditional sense. Instead, its biocompatibility allows it to integrate with biological tissues without eliciting significant immune responses, making it suitable for use in implants and prosthetic devices. The presence of titanium ions can influence biological processes, including cell proliferation and differentiation.

Pharmacodynamics

Titanium itself does not exhibit pharmacodynamics as it is not administered as a drug. Its interactions within biological systems are primarily mechanical and structural, providing support and stability in orthopedic and dental applications. The biocompatibility of titanium allows for favorable tissue integration and reduced rejection rates compared to other materials.

Pharmacokinetics

As titanium is not a pharmacological agent, traditional pharmacokinetic parameters such as absorption, distribution, metabolism, and excretion do not apply. Titanium is typically utilized in solid forms, such as implants, where it remains localized and does not undergo metabolism or systemic circulation.

Pregnancy

There is limited data on the use of titanium during pregnancy. Consult a healthcare professional before use.

Breast-feeding

There is limited data on the excretion of titanium in breast milk. Consult a healthcare professional before use.

Storage

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

Pregnancy

No specific data available, consult a healthcare professional.

Breast-feeding

No specific data available, consult a healthcare professional.

Storage

Store in a cool, dry place away from light.

Mechanism of action

Clarithromycin is first metabolized to 14-OH clarithromycin, which is active and works synergistically with its parent compound. Like other macrolides, it then penetrates bacteria cell wall and reversibly binds to domain V of the 23S ribosomal RNA of the 50S subunit of the bacterial ribosome, blocking translocation of aminoacyl transfer-RNA and polypeptide synthesis. Clarithromycin also inhibits the hepatic microsomal CYP3A4 isoenzyme and P-glycoprotein, an energy-dependent drug efflux pump. Clarithromycin usually is bacteriostatic, although it may be bactericidal in high concentrations or against highly susceptible organisms. Bactericidal activity has been observed against Streptococcus pyogenes, S. pneumoniae, Haemophilus influenzae, and Chlamydia trachomatis. Clarithromycin inhibits protein synthesis in susceptible organisms by penetrating the cell wall and binding to 50S ribosomal subunits, thereby inhibiting translocation of aminoacyl transfer-RNA and inhibiting polypeptide synthesis. The site of action of clarithromycin appears to be the same as that of erythromycin, clindamycin, lincomycin, and chloramphenicol.

Pharmacodynamics

Clarithromycin is a macrolide antibiotic whose spectrum of activity includes many gram-positive (<i>Staphylococcus aureus, S. pneumoniae, and S. pyogenes</i>) and gram-negative aerobic bacteria (<i>Haemophilus influenzae, H. parainfluenzae, and Moraxella catarrhalis</i>), many anaerobic bacteria, some mycobacteria, and some other organisms including <i>Mycoplasma, Ureaplasma, Chlamydia, Toxoplasma</i>, and <i>Borrelia</i>. Other aerobic bacteria that clarithromycin has activity against include <i>C. pneumoniae and M. pneumoniae</i>. Clarithromycin has an in-vitro activity that is similar or greater than that of erythromycin against erythromycin-susceptible organisms. Clarithromycin is usually bacteriostatic, but may be bactericidal depending on the organism and the drug concentration.

Mechanism of action

Ethylene glycol toxicity results from its metabolism to glycolic acid and other toxic metabolites. The accumulation of glycolate and the elimination kinetics of ethylene glycol and its metabolites are not well understood, so studies with male Sprague-Dawley rats and mixed breed dogs have been carried out. Ethylene glycol was administered by gavage to rats and dogs which were placed in metabolic cages for urine and blood sample collection at timed intervals. The peak plasma level of ethylene glycol occurred at 2 hr after dosing and that of glycolate between 4-6 hr. The rate of ethylene glycol elimination was somewhat faster in rats with a half-life of 1.7 hr compared to 3.4 hr in dogs. The maximum plasma level of glycolate was greater in rats although the pattern of accumulation was similar to that in dogs. Glycolate disappeared from the plasma at the same time as ethylene glycol, suggesting a slower rate of elimination of the metabolite than that of ethylene glycol. Renal excretion of ethylene glycol was an important route for its elimination accounting for 20-30% of the dose. Renal excretion of glycolate represented about 5% of the dose. Ethylene glycol induced an immediate, but short lived diuresis compared to that in control rats. Minimal clinical effects (mild acidosis with no sedation) were noted at these doses of ethylene glycol (1-2 g/kg) in both rats and dogs. The results indicate that the toxicokinetics of ethylene glycol and glycolate were similar in both species. The effect of 0.35 to 0.8 mmol/kg glycolic acid and 1.0 to 4.4 mmol/kg sodium glycolate on cyclopropane-epinephrine induced cardiac arrhythmias was examined using dogs. Doses of 0.35 to 0.5 mmol/kg glycolic acid increased the duration of arrhythmias in the 13 dogs tested, whereas doses >0.5 mmol/kg decreased or totally eliminated the arrhythmias in each of 11 dogs. Depression was observed for many of the dogs at higher doses. Sodium glycolate was much less effective in decreasing the arrhythmias, with 3 mmol/kg being required and its action being transient.

Mechanism of action

Ethylene glycol is metabolized by alcohol dehydrogenase to glycoaldehyde, which is then metabolized to glycolic, glyoxylic, and oxalic acids. These acids, along with excess lactic acid are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic and glyoxylic acids.

Mechanism of action

Chlormequat chloride has been reported in the literature to act at the nicotinic receptor site of the neuromuscular junction. The test material may act as a depolarizing agent at this site, leading to muscular excitation followed by muscle weakness. Acute toxicity may lead to respiratory arrest. Acute toxicity of chlormequat chloride has also been reported to differ by species, which is likely due to sensitivity to depolarizing neuromuscular blockers.

Mechanism of action

QUINOLINE BINDS TO RNA, DNA & CERTAIN POLYRIBONUCLEOTIDES IN PRESENCE OF NADPH & RAT LIVER MICROSOMES. BINDING WAS PRONOUNCED WITH HELP OF SOME INDUCERS OF MICROSOMAL MONOOXYGENASE SYSTEM. BINDING REACTION REQUIRED NADPH & WAS INHIBITED BY CARBON MONOXIDE, ANILINE, 7,8-BENZOFLAVONE, METHYRAPONE OR SKF 525A. QUINOLINE BOUND PREFERENTIALLY TO POLY(A), POLY(C), POLY(G) & POLY(X), BUT NEGLIGIBLY TO POLY(U) & POLY(I). MOST OF QUINOLINE RESIDUES OF THE ADDUCTS, REGARDLESS OF KIND OF POLYNUCLEOTIDES USED WERE RELEASED BY ACID OR ALKALI AT 100 °C IN FORM OF 3-HYDROXYQUINOLINE. THE 2,3- OR 3,4-EPOXY DERIVATIVE OF QUINOLINE APPARENTLY IS THE REACTIVE INTERMEDIATE FOR NUCLEIC ACID MODIFICATION.

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.