Mycept 250

Indications

• Used as a disintegrant in tablet formulations
• Enhances the bioavailability of active pharmaceutical ingredients

Dosage

Children: Refer to the specific formulation guidelines, as dosage will vary based on the active ingredient and formulation type.

Adults: Refer to the specific formulation guidelines, as dosage will vary based on the active ingredient and formulation type.

Mechanism of action

Croscarmellose sodium works by swelling and absorbing water when it comes into contact with gastrointestinal fluids. This swelling leads to the rapid disintegration of the tablet or capsule matrix, facilitating the release and absorption of the active pharmaceutical ingredients.

Pharmacodynamics

Croscarmellose sodium is classified as a superdisintegrant. Its ability to rapidly disintegrate solid dosage forms can significantly enhance the dissolution rate of the active ingredient, which is crucial for achieving therapeutic effects in a timely manner.

Pharmacokinetics

Croscarmellose sodium is not absorbed in the gastrointestinal tract and does not exert pharmacological effects in the body. It is considered non-toxic and is excreted unchanged. Its main role is as an excipient, influencing the formulation's characteristics rather than the pharmacokinetics of the active ingredients.

Precautions

• Use with caution in patients with known hypersensitivity to croscarmellose or its components.

Pregnancy

Safety in pregnancy has not been established. Use only if clearly needed.

Breast-feeding

Caution is advised when using during breastfeeding, as safety has not been established.

Storage

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

Formulations

• Powder
• Granules

Indications

• Organ transplantation (kidney, heart, liver)
• Autoimmune diseases (lupus nephritis, rheumatoid arthritis)

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Mofetil acts primarily by inhibiting the enzyme inosine monophosphate dehydrogenase (IMPDH), which is crucial in the de novo synthesis of purines. This action selectively affects lymphocytes, as they are reliant on this pathway for proliferation. By reducing the availability of purines, mofetil hinders the proliferation of T and B lymphocytes, thereby exerting its immunosuppressive effects.

Pharmacodynamics

The immunosuppressive effects of mofetil are dose-dependent. The reduction of lymphocyte proliferation leads to decreased antibody production and a lower risk of acute rejection in transplant patients. Mofetil also has anti-inflammatory properties, which can be beneficial in autoimmune disorders, helping to mitigate tissue damage caused by an overactive immune response.

Pharmacokinetics

Mofetil is rapidly absorbed following oral administration, with peak plasma concentrations occurring within 1 to 2 hours. It has a bioavailability of approximately 94% under fasting conditions. The drug is extensively metabolized in the liver, primarily by UDP-glucuronosyltransferases, leading to the formation of mycophenolic acid. The elimination half-life of mofetil is about 16 to 18 hours. It is excreted mainly via urine, with approximately 90% of the dose eliminated as metabolites.

Contra-indications

• Hypersensitivity to mofetil or any component of the formulation
• Pregnancy
• Active infections

Adverse effects

• Gastrointestinal disturbances such as nausea, vomiting, and diarrhea
• Increased risk of infections due to immunosuppression
• Hematological effects including leukopenia and thrombocytopenia
• Liver enzyme elevations
• Headache
• Hypertension

Interactions

• Increased risk of infections when combined with other immunosuppressants
• May interact with drugs that are metabolized by the liver, particularly cytochrome P450 enzymes
• Avoid concomitant use with live vaccines due to immunosuppressive effects

Precautions

• Monitor for signs of infection due to immunosuppressive effects
• Liver function tests should be performed regularly
• Use with caution in patients with pre-existing hepatic or renal impairment
• Consider potential for drug interactions

Pregnancy

Mofetil is contraindicated in pregnancy due to potential teratogenic effects.

Breast-feeding

Mofetil is excreted in breast milk; caution is advised if used during breastfeeding.

Storage

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

Formulations

• Oral tablets
• Oral suspension
• Injection

Indications

• Prevention of organ rejection in kidney transplants
• Prevention of organ rejection in heart transplants
• Prevention of organ rejection in liver transplants

Dosage

Children: For paediatric patients, mycophenolate dosing is based on body surface area and typically starts at 600 mg/m² taken twice daily. Adjustments may be made according to clinical response. For specific paediatric dosing recommendations, refer to BNF for Children.

Adults: The usual initial dose of mycophenolate mofetil for adults is 1 g taken twice daily, which may be adjusted based on clinical response and tolerability. Dosage can vary based on the specific transplant type and patient condition. Refer to BNF for detailed dosing guidelines.

Mechanism of action

Mycophenolate works by inhibiting inosine monophosphate dehydrogenase (IMPDH), which is crucial for the de novo synthesis pathway of purine nucleotides in lymphocytes. This inhibition selectively affects lymphocytes, as they rely on this pathway for proliferation more than other cell types, leading to reduced lymphocyte counts and a suppressed immune response.

Pharmacodynamics

The pharmacodynamics of mycophenolate involve its selective inhibition of lymphocyte activation and proliferation, which is critical in preventing acute rejection in organ transplantation. By decreasing the number of activated T and B lymphocytes, mycophenolate effectively reduces the likelihood of graft rejection while maintaining some degree of immune function to protect against infections.

Pharmacokinetics

Mycophenolate is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 1-2 hours. It undergoes extensive first-pass metabolism in the liver, resulting in the active metabolite mycophenolic acid. The drug is primarily eliminated via glucuronidation and is excreted in urine. Its plasma half-life is approximately 16-18 hours, although this can vary based on individual patient factors and concurrent medications.

Contra-indications

• Hypersensitivity to mycophenolate or any of its components
• Pregnancy (except in specific cases where benefits outweigh risks)

Adverse effects

• Gastrointestinal disturbances (nausea, vomiting, diarrhea)
• Increased risk of infections
• Hematological toxicity (such as leukopenia, anemia, thrombocytopenia)
• Headache
• Hypertension
• Elevated liver enzymes

Interactions

• rifampicin+mycophenolate: Moderate (decreases concentration)
• mycophenolate+aciclovir: Unknown (increases risk of haematological toxicity)
• isavuconazole+mycophenolate: Unknown (increases exposure)
• mycophenolate+ganciclovir: Unknown (increases risk of haematological toxicity)
• live vaccines+mycophenolate: Unknown (increases risk of generalised infection, possibly life-threatening)
• mycophenolate+valaciclovir: Unknown (increases risk of haematological toxicity)
• mycophenolate+valganciclovir: Unknown (increases risk of haematological toxicity)

Precautions

• Monitor for signs of infection due to immunosuppression
• Regular blood count monitoring to detect hematological toxicity
• Use with caution in patients with renal impairment
• Assess risk of malignancy and cardiovascular disease in long-term use

Pregnancy

Use in pregnancy should be avoided unless the potential benefits justify the risks to the fetus.

Breast-feeding

It is not known whether mycophenolate is excreted in human milk. Caution is advised when administered to nursing women.

Storage

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

Formulations

• Mycophenolate mofetil capsules
• Mycophenolate mofetil tablets
• Mycophenolate mofetil oral suspension

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 as a binder in tablet formulations
• Serves as a disintegrant to improve drug release
• Acts as a thickening agent in liquid formulations
• Enhances bioavailability of poorly soluble drugs

Dosage

Children: Dosage is dependent on the specific formulation and intended use. Refer to formulation guidelines for appropriate concentrations.

Adults: Dosage is dependent on the specific formulation and intended use. Refer to formulation guidelines for appropriate concentrations.

Mechanism of action

Pregelatinised starch acts primarily as a thickening agent and binder in pharmaceutical formulations. When mixed with water, it swells and forms a gel-like consistency, which helps in the uniform distribution of active ingredients and enhances their release and absorption in the gastrointestinal tract. Its ability to gel enables better disintegration of tablets upon administration, facilitating the dissolution of the drug.

Pharmacodynamics

The pharmacodynamics of pregelatinised starch is closely related to its physical properties as a polymer. Upon contact with water, it hydrates and expands, creating a viscous solution that can improve the release profile of drugs. This can lead to enhanced dissolution rates of poorly soluble compounds, improving their bioavailability. Additionally, it can impact the stability and shelf-life of formulations by providing a protective matrix for active ingredients.

Pharmacokinetics

Pregelatinised starch is not absorbed systemically as it primarily acts as an excipient. It undergoes gastrointestinal transit without significant degradation. Its function is to facilitate the release and absorption of the active pharmaceutical ingredients in the formulation rather than exhibiting pharmacokinetic properties of its own.

Pregnancy

Pregelatinised starch is generally considered safe for use during pregnancy, but it is recommended to consult a healthcare provider before use.

Breast-feeding

Pregelatinised starch is considered safe during breastfeeding, but it is advisable to seek medical advice.

Storage

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

Formulations

• Powder
• Capsules
• Tablets

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

• 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