LAMSEV 800

Indications

• Hyperphosphataemia in patients on haemodialysis
• Hyperphosphataemia in patients on peritoneal dialysis
• Hyperphosphataemia in patients with chronic kidney disease not on dialysis who have elevated serum phosphate levels

Dosage

Children: Dose to be adjusted according to the requirements of the patient, taken with meals. Consult product literature for specific dosing information.

Adults: Initially 2.4–4.8 g daily in 3 divided doses, to be taken with meals and adjusted according to serum-phosphate concentration every 2–4 weeks. The usual maintenance dose is 6 g daily in 3 divided doses.

Mechanism of action

Sevelamer works by binding phosphate in the gastrointestinal tract, preventing its absorption into the bloodstream. This mechanism is crucial for patients with renal impairment who cannot adequately excrete phosphate, leading to hyperphosphataemia. By reducing intestinal phosphate absorption, sevelamer helps in maintaining normal serum phosphate levels.

Pharmacodynamics

Sevelamer's phosphate-binding ability helps to lower serum phosphate levels, which is vital in patients with chronic kidney disease. Elevated serum phosphate can lead to cardiovascular complications and bone mineral disorders. The pharmacodynamic profile of sevelamer indicates a dose-dependent effect on serum phosphate reduction, which is monitored and adjusted based on individual patient needs.

Pharmacokinetics

Sevelamer is not absorbed systemically; it remains in the gastrointestinal lumen where it binds phosphate. The pharmacokinetic properties indicate that peak phosphate-binding occurs shortly after administration, particularly when taken with meals. The elimination of sevelamer is primarily through feces, as it does not undergo significant metabolic transformation or systemic absorption.

Contra-indications

• haemochromatosis
• iron accumulation disorders
• bowel obstruction

Adverse effects

• constipation
• diarrhoea
• gastrointestinal discomfort
• nausea
• vomiting
• abnormal taste
• tooth discolouration

Interactions

• calcium salts
• iron
• roxadustat (modestly decreases exposure)

Precautions

• gastrointestinal disorders
• hepatic disorders
• major surgery
• peritonitis in the last 3 months

Pregnancy

Manufacturer advises use only if potential benefit outweighs risk.

Breast-feeding

Unlikely to be present in milk, however, manufacturer advises to avoid.

Storage

Store at room temperature, away from moisture and heat.

Formulations

• {'name': 'Renvela', 'form': 'oral powder sachets', 'strength': '2.4 g', 'pack_size': '60 sachets'}
• {'name': 'Renvela', 'form': 'chewable tablets', 'strength': '800 mg', 'pack_size': '90 tablets'}

Indications

• Cerebral edema
• Elevated intracranial pressure
• Acute kidney injury
• Oliguria
• Glaucoma
• Renal function diagnostic aid

Dosage

Adults: For cerebral edema, administer 0

Mechanism of action

Mannitol elevates blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluid, into interstitial fluid and plasma. This action reduces cerebral edema and intracranial pressure. As a diuretic, it increases the osmolality of glomerular filtrate, leading to increased urinary excretion of water and preventing sodium and chloride reabsorption in the renal tubules. Mannitol also facilitates the urinary excretion of toxic substances and can help in assessing renal function by measuring glomerular filtration rate (GFR).

Pharmacodynamics

Mannitol is classified as an osmotic diuretic. It is chemically similar to other sugar alcohols but has a unique ability to promote diuresis by remaining unabsorbed in the renal tubules. Its use is indicated for conditions associated with increased body fluids, such as cerebral edema and glaucoma. Mannitol may be combined with other diuretics to enhance diuretic efficacy. Inhaled formulations are used in cystic fibrosis, though they may cause bronchospasm and hemoptysis.

Pharmacokinetics

Mannitol is freely filtered by the glomeruli with less than 10% tubular reabsorption, which allows for its urinary excretion rate to serve as a measurement of GFR. It does not undergo significant metabolism and is eliminated primarily through the kidneys. The onset of action occurs within 30 to 60 minutes after intravenous administration, with effects lasting for several hours. Administration may require monitoring of renal function and fluid balance.

Contra-indications

• Anuria
• Severe dehydration
• Severe renal impairment
• Intracranial bleeding

Adverse effects

• Asthenia
• Gastrointestinal disturbances
• Dry mouth
• Confusion
• Visual impairment
• Hypotension
• Electrolyte imbalances
• Pulmonary edema
• Hemoptysis (with inhalation use)
• Bronchospasm (with inhalation use)

Interactions

• Potassium-sparing diuretics may increase the risk of hyperkalemia
• Other diuretics may have additive effects
• Caution with nephrotoxic agents

Precautions

• Caution in patients with diabetes mellitus
• Caution in the elderly
• Caution in patients with gout
• Caution in patients with hepatic impairment
• Monitor renal function and electrolytes regularly
• May cause blue fluorescence of urine

Pregnancy

Manufacturer advises avoid due to potential toxicity in animal studies.

Breast-feeding

Manufacturer advises avoid due to lack of information available.

Storage

Store in a cool, dry place, away from light. Do not freeze.

Formulations

• Solution for injection
• Inhalation powder
• Oral solution

Indications

• Hypertension
• Edema associated with heart failure
• Edema due to renal disorders
• Edema related to liver cirrhosis

Dosage

Children: Refer to the BNF for Children for appropriate dosing information in pediatric patients.

Adults: Refer to the BNF for specific dosing guidelines, as doses typically range from 25 to 100 mg daily, depending on the condition being treated.

Mechanism of action

Hydrochlorothiazide is transported into epithelial cells of the distal convoluted tubule via organic anion transporters OAT1, OAT3, and OAT4. It inhibits the sodium-chloride symporter (SLC12A3), which is responsible for the reabsorption of sodium and chloride ions. This inhibition reduces the concentration gradient across the epithelial cells, leading to decreased reabsorption of water and increased diuresis.

Pharmacodynamics

Hydrochlorothiazide prevents sodium and water reabsorption from the distal convoluted tubule, resulting in increased urine output. It has a wide therapeutic window, with individual dosing typically ranging from 25 to 100 mg. Caution is advised in patients with impaired kidney or liver function due to potential changes in drug metabolism and excretion.

Pharmacokinetics

Hydrochlorothiazide is well absorbed from the gastrointestinal tract and has a bioavailability of approximately 60-80%. It is primarily excreted unchanged in the urine. The drug has a half-life of about 6-15 hours, allowing for once-daily dosing in many cases. Its effects can last for up to 24 hours, making it suitable for managing chronic conditions.

Contra-indications

• Anuria
• Hypersensitivity to hydrochlorothiazide or any component of the formulation
• Severe renal impairment

Adverse effects

• Electrolyte imbalances (e.g., hypokalemia, hyponatremia)
• Dizziness
• Headache
• Nausea
• Vomiting
• Rash
• Increased uric acid levels leading to gout
• Pancreatitis
• Hyperglycemia

Interactions

• Increased risk of hypotension with other antihypertensive agents
• May enhance the effects of loop diuretics and thiazide diuretics
• Lithium levels may increase when used with hydrochlorothiazide
• Non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the diuretic effect
• Corticosteroids may increase the risk of hypokalemia

Precautions

• Use with caution in patients with hepatic impairment
• Monitor renal function prior to and during therapy
• Assess for electrolyte imbalances regularly
• Consider potential interaction with other drugs affecting electrolyte levels

Pregnancy

Hydrochlorothiazide should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It is not recommended for routine use.

Breast-feeding

Hydrochlorothiazide is excreted in breast milk. Caution is advised when administered to nursing mothers.

Storage

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

Formulations

• Tablets (various strengths, commonly 12.5mg, 25mg, 50mg)
• Oral solution

Indications

• Used as an excipient in pharmaceutical formulations
• Improves solubility and bioavailability of active ingredients

Dosage

Children: Refer to specific product formulations for dosing guidance, as behenate is primarily used as an excipient.

Adults: Refer to specific product formulations for dosing guidance, as behenate is primarily used as an excipient.

Mechanism of action

Behenate functions mainly as a surfactant and emulsifying agent. It interacts with lipids and cellular membranes, enhancing the solubility of poorly soluble drugs and facilitating their absorption in the gastrointestinal tract. By modifying the physicochemical properties of drug formulations, behenate improves the pharmacokinetic profiles of certain medications.

Pharmacodynamics

The pharmacodynamics of behenate are primarily linked to its role as an excipient rather than an active pharmaceutical ingredient. Its interaction with cellular membranes can lead to altered absorption rates and enhanced solubility of co-administered drugs. Its effects are dependent on the concentration used within the formulation and the properties of the active ingredients it accompanies.

Pharmacokinetics

As behenate is usually employed in formulations rather than used alone, specific pharmacokinetic data is limited. However, it is known to be absorbed and metabolized similarly to other long-chain fatty acids. The absorption through the gastrointestinal tract is influenced by the presence of bile acids and the overall lipid content of the diet. Metabolism typically involves the conversion to various metabolites through beta-oxidation in the liver.

Mechanism of action

Carbonate ions participate in buffering reactions that help maintain pH homeostasis in biological systems. They can react with acids to form bicarbonate and carbon dioxide, thus neutralizing excess acidity in the body. This mechanism is crucial in processes such as respiration and metabolism.

Pharmacodynamics

As a buffer, carbonate helps to stabilize pH levels in different biological environments, preventing excessive acidity or alkalinity that could impair cellular functions. It is involved in the transport of carbon dioxide in the blood and plays a role in maintaining the acid-base equilibrium necessary for physiological processes.

Pharmacokinetics

Carbonate ions are readily absorbed in the gastrointestinal tract when ingested and can be found in various body fluids. They are involved in the bicarbonate buffering system, where they are converted to bicarbonate (HCO3-) and carbon dioxide (CO2) through reactions with acids. The kidneys regulate the levels of bicarbonate and carbonate in the body, excreting or reabsorbing them as needed to maintain homeostasis.

Pregnancy

There is no specific information available regarding the use of carbonate compounds during pregnancy. Consult a healthcare provider for advice.

Breast-feeding

There is no specific information available regarding the use of carbonate compounds while breastfeeding. Consult a healthcare provider for advice.

Storage

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

Indications

• Zinc deficiency
• Wound healing
• Immune support
• Diarrhea in children
• Acne treatment

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines tailored to pediatric patients.

Adults: Refer to the BNF for specific dosing guidelines based on the condition being treated.

Mechanism of action

Clear acts by chelating with biological molecules, facilitating the transfer of electrons and maintaining structural integrity of proteins and enzymes. The zinc component is crucial for various biochemical pathways and is involved in DNA synthesis, immune function, and cell division.

Pharmacodynamics

The pharmacodynamic effects of Clear are primarily attributed to zinc's role in numerous physiological processes. Zinc is a cofactor for over 300 enzymes and is vital for maintaining cellular function, promoting wound healing, and modulating immune response. Its antioxidant properties also help to mitigate oxidative stress in the body.

Pharmacokinetics

Clear is absorbed in the gastrointestinal tract, with bioavailability varying based on the formulation. The distribution of zinc in the body is primarily in muscle and bone, with renal excretion being the main route of elimination. The half-life of zinc can vary based on dietary intake and individual metabolism.

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

• Used as a disintegrant in tablet formulations
• Facilitates the release of active pharmaceutical ingredients in oral dosage forms

Dosage

Children: Refer to specific formulation guidelines as dosing is based on the formulation and not typically provided for excipients like crosspovidone.

Adults: Refer to specific formulation guidelines as dosing is based on the formulation and not typically provided for excipients like crosspovidone.

Mechanism of action

Crosspovidone functions as a disintegrant by absorbing water and swelling upon contact with moisture, which disrupts the tablet structure and leads to rapid disintegration. This mechanism increases the surface area of the active ingredient, allowing for faster dissolution and absorption in the gastrointestinal tract.

Pharmacodynamics

The pharmacodynamics of crosspovidone are primarily related to its physical properties rather than specific biochemical interactions. It aids in the disintegration and dissolution processes of tablets, enhancing the bioavailability of the active pharmaceutical ingredients. The effectiveness of crosspovidone as a disintegrant can depend on factors such as the formulation, the presence of other excipients, and the manufacturing process.

Pharmacokinetics

Crosspovidone is not absorbed systemically as it is used in formulations as an excipient. It remains in the gastrointestinal tract where it performs its function as a disintegrant. Its elimination is not applicable as it does not enter the systemic circulation. The biocompatibility of crosspovidone is well established, and it is generally recognized as safe for use in pharmaceuticals.

Pregnancy

Crosspovidone is generally considered safe for use in pregnancy as it is not systemically absorbed, but clinical judgement should be applied.

Breast-feeding

Crosspovidone is not systemically absorbed and is unlikely to pose a risk to a breastfeeding infant.

Storage

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

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

• 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

Indications

• Ophthalmic solutions
• Topical formulations
• Oral solid dosage forms
• Stabilizer in various pharmaceutical preparations

Dosage

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

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

Mechanism of action

Hydroxypropylcellulose functions primarily as a viscosity-increasing agent. When dissolved in water, it forms a gel-like consistency that helps to stabilize formulations. Its mechanism is related to its ability to create a hydrated film, which can enhance the retention of active ingredients and improve the delivery of medications to the targeted area, particularly in ocular applications.

Pharmacodynamics

The pharmacodynamic properties of hydroxypropylcellulose are primarily related to its physical characteristics rather than specific receptor interactions. It exhibits properties such as gel formation and moisture retention, which can enhance the stability and effectiveness of drug formulations. Its viscosity can influence the release rates of active pharmaceutical ingredients, thereby affecting the overall therapeutic effect.

Pharmacokinetics

Hydroxypropylcellulose is not systemically absorbed when used in pharmaceutical applications, as it acts locally at the site of application. Its pharmacokinetics involves dissolution and gel formation in the presence of water, with no significant metabolic pathways or excretion processes, given its large molecular structure. The duration of action is primarily influenced by the formulation and the concentration used.

Pregnancy

Hydroxypropylcellulose is generally considered safe for use during pregnancy as it is not systemically absorbed. However, it should be used only when clearly needed.

Breast-feeding

Hydroxypropylcellulose is not absorbed systemically and is considered safe for use during breastfeeding.

Storage

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

Formulations

• Ophthalmic solutions
• Topical gels
• Oral capsules
• Powders for reconstitution

Indications

• Alcohol use disorder
• Antiseptic for skin disinfection
• Solvent for drug formulations
• Sedative in certain medicinal contexts

Dosage

Children: Refer

Adults: Refer to the BNF for specific dosing guidance.

Mechanism of action

Ethanol affects the brain’s neurons by altering their membranes, ion channels, enzymes, and receptors. It binds to GABA, serotonin, acetylcholine, and NMDA receptors, enhancing the inhibitory effects of GABA at GABAa receptors while inhibiting NMDA receptor functioning. This results in a sedative effect and can disrupt osmotic balance across cell membranes, contributing to its anti-infective properties by acting as a dehydrating agent.

Pharmacodynamics

Ethanol induces cell injury through dehydration and precipitating cytoplasmic components, which accounts for its bactericidal and antifungal properties. It produces neurolysis and nerve degeneration when in close proximity to nerve tissues. Ethanol is metabolized predominantly by the liver enzyme alcohol dehydrogenase, leading to its eventual oxidation and elimination from the body. Its sedative effects are attributed to modulation of neurotransmitter receptor activities, particularly enhancing GABA receptor actions.

Pharmacokinetics

Ethanol is rapidly absorbed from the gastrointestinal tract, with peak blood concentrations occurring within 30 to 90 minutes after consumption. It is distributed throughout body water, influencing its volume of distribution. Ethanol is primarily metabolized in the liver, with approximately 90 to 98% being oxidized. The metabolic pathways involve alcohol dehydrogenase and the microsomal ethanol-oxidizing system, leading to the production of acetaldehyde and subsequent elimination. Ethanol's elimination half-life can vary significantly based on individual factors and the amount consumed.

Adverse effects

• Drowsiness
• Dizziness
• Nausea
• Vomiting
• Headache
• Respiratory depression
• Hypotension
• Dependency and withdrawal symptoms

Interactions

• May enhance the effects of central nervous system depressants
• May interact with medications that are metabolized by liver enzymes
• May affect the efficacy of certain medications like anticoagulants and antiepileptics

Precautions

• Use with caution in patients with a history of alcohol use disorder
• Caution in patients with liver disease
• Monitor for signs of sedation and respiratory depression
• Avoid in combination with other sedatives and tranquilizers

Pregnancy

Ethanol is contraindicated during pregnancy due to the risk of fetal alcohol syndrome and other developmental disorders.

Breast-feeding

Ethanol is excreted in breast milk; caution is advised as it may affect the infant.

Storage

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

Formulations

• Oral solution
• Topical solution
• Injectable solution

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.

Indications

• Potential role in bone health
• Support for connective tissue formation
• May aid in mineral metabolism

Dosage

Children: There is no established clinical dosage for silicon in paediatric populations, as it is not classified as an essential nutrient.

Adults: There is no established clinical dosage for silicon in adults, as it is not classified as an essential nutrient.

Mechanism of action

Silicon is believed to enhance the synthesis of glycosaminoglycans and collagen, which are important for the structural integrity of connective tissues. It may also influence the activity of certain enzymes involved in bone mineralization, thus playing a role in maintaining bone density and health.

Pharmacodynamics

The pharmacodynamics of silicon is not fully elucidated; however, it is thought to involve the modulation of bone metabolism and the promotion of connective tissue health. Silicon may have a synergistic effect with other minerals, such as calcium and magnesium, aiding in their utilization and metabolism in the body.

Pharmacokinetics

The pharmacokinetics of silicon is complex, as it is not absorbed through typical gastrointestinal pathways. Instead, silicon is thought to be taken up in the form of silicates and then distributed throughout the body, particularly in connective tissues. The elimination of silicon occurs primarily through renal excretion, with some variations depending on dietary intake and individual metabolism.

Pregnancy

Silicon is generally considered safe during pregnancy, as it is a naturally occurring element in the human body. However, specific recommendations regarding supplementation should be followed based on the advice of a healthcare provider.

Breast-feeding

Silicon is present in breast milk in small amounts. Its safety during breastfeeding is generally regarded as acceptable, although supplementation should be approached with caution and under medical advice.

Storage

Silicon should be stored in a cool, dry place, protected from light and moisture. Follow specific storage recommendations provided by the manufacturer if available.

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.

Mechanism of action

Mannitol is an osmotic diuretic that is metabolically inert in humans and occurs naturally, as a sugar or sugar alcohol, in fruits and vegetables. Mannitol elevates blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluid, into interstitial fluid and plasma. As a result, cerebral edema, elevated intracranial pressure, and cerebrospinal fluid volume and pressure may be reduced. As a diurectic mannitol induces diuresis because it is not reabsorbed in the renal tubule, thereby increasing the osmolality of the glomerular filtrate, facilitating excretion of water, and inhibiting the renal tubular reabsorption of sodium, chloride, and other solutes. Mannitol promotes the urinary excretion of toxic materials and protects against nephrotoxicity by preventing the concentration of toxic substances in the tubular fluid. As an Antiglaucoma agent mannitol levates blood plasma osmolarity, resulting in enhanced flow of water from the eye into plasma and a consequent reduction in intraocular pressure. As a renal function diagnostic aid mannitol is freely filtered by the glomeruli with less than 10% tubular reabsorption. Therefore, its urinary excretion rate may serve as a measurement of glomerular filtration rate (GFR). The exact mechanism of action of inhaled mannitol in the symptomatic maintenance treatment of cystic fibrosis remains unclear. It is hypothesized that mannitol produces an osmotic gradient across the airway epithelium that draws fluid into the extracellular space and alters the properties of the airway surface mucus layer, allowing easier mucociliary clearance. MANNITOL IS.../USED/ IN PROPHYLAXIS OF ACUTE RENAL FAILURE. IT IS USED FOR THIS PURPOSE IN CONDITIONS AS DIVERSE AS CARDIOVASCULAR OPERATIONS, SEVERE TRAUMATIC INJURY, OPERATIONS IN THE PRESENCE OF SEVERE JAUNDICE, AND MGMNT OF HEMOLYTIC TRANSFUSION REACTIONS. IN EACH OF THESE CONDITIONS, A PRECIPITOUS FALL IN THE FLOW OF URINE MAY BE ANTICIPATED EITHER AS THE RESULT OF AN ACUTELY REDUCED FILTRATION RATE OR FROM ACUTE CHANGES IN TUBULAR PERMEABILITY. THE LATTER MAY BE CONSEQUENCE OF THE PRESENCE OF NOXIOUS AGENT WITHIN THE TUBULAR FLUID IN EXCESSIVELY HIGH CONCN, IN SOME INSTANCES SUFFICIENT TO RESULT IN ACTUAL PRECIPITATION. IN THESE SITUATIONS, MANNITOL EXERTS OSMOTIC EFFECT WITHIN THE TUBULAR FLUID, INHIBITS WATER REABSORPTION, & MAINTAINS THE RATE OF URINE FLOW. ...CONCN OF TOXIC AGENT WITHIN TUBULAR FLUID DOES NOT REACH EXCESSIVELY HIGH LEVELS THAT OTHERWISE WOULD HAVE BEEN ACHIEVED BY MORE COMPLETE REABSORPTION OF WATER. ...EVEN THOUGH /GLOMERULAR/ FILTRATION RATE IS REDUCED, MANNITOL IS STILL FILTERED @ GLOMERULUS. THE TUBULAR IMPERMEABILITY TO MANNITOL IS NOT ALTERED BY ACUTE RENAL ISCHEMIA OF SHORT DURATION. HENCE, THE MANNITOL THAT IS FILTERED IS ALSO EXCRETED IN THE VOIDED URINE. UNREABSORBED SOLUTE LIMITS BACK DIFFUSION OF WATER. ...URINE VOL CAN BE MAINTAINED EVEN IN PRESENCE OF DECR GLOMERULAR FILTRATION.

Pharmacodynamics

Chemically, mannitol is an alcohol and a sugar, or a polyol; it is similar to xylitol or sorbitol. However, mannitol has a tendency to lose a hydrogen ion in aqueous solutions, which causes the solution to become acidic. For this reason, it is not uncommon to add a substance to adjust its pH, such as sodium bicarbonate. Mannitol is commonly used to increase urine production (diuretic). It is also used to treat or prevent medical conditions that are caused by an increase in body fluids/water (e.g., cerebral edema, glaucoma, kidney failure). Mannitol is frequently given along with other diuretics (e.g., furosemide, chlorothiazide) and/or IV fluid replacement. Inhaled mannitol has the possibility to cause bronchospasm and hemoptysis; the occurrence of either should lead to discontinuation of inhaled mannitol.

Mechanism of action

Hydrochlorothiazide is transported from the circulation into epithelial cells of the distal convoluted tubule by the organic anion transporters OAT1, OAT3, and OAT4. From these cells, hydrochlorothiazide is transported to the lumen of the tubule by multidrug resistance associated protein 4 (MRP4). Normally, sodium is reabsorbed into epithelial cells of the distal convoluted tubule and pumped into the basolateral interstitium by a sodium-potassium ATPase, creating a concentration gradient between the epithelial cell and the distal convoluted tubule that promotes the reabsorption of water. Hydrochlorothiazide acts on the proximal region of the distal convoluted tubule, inhibiting reabsorption by the sodium-chloride symporter, also known as Solute Carrier Family 12 Member 3 (SLC12A3). Inhibition of SLC12A3 reduces the magnitude of the concentration gradient between the epithelial cell and distal convoluted tubule, reducing the reabsorption of water.

Pharmacodynamics

Hydrochlorothiazide prevents the reabsorption of sodium and water from the distal convoluted tubule, allowing for the increased elimination of water in the urine. Hydrochlorothiazide has a wide therapeutic window as dosing is individualized and can range from 25-100mg. Hydrochlorothiazide should be used with caution in patients with reduced kidney or liver function.

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

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

It has very good absorptive properties.