Supertrim

Indications

• Bacterial infections
• Urinary tract infections
• Respiratory tract infections
• Prophylaxis of recurrent urinary tract infections

Dosage

Children: For children aged 6 weeks to 5 months: 4 mg/kg twice daily (max. 200 mg). For children 6 months to 5 years: 4 mg/kg twice daily (max. 200 mg). For children 6–11 years: 4 mg/kg twice daily (max. 200 mg). For children

Adults: 200 mg twice daily.

Mechanism of action

Trimethoprim is a reversible inhibitor of dihydrofolate reductase, an enzyme that catalyzes the formation of tetrahydrofolic acid from dihydrofolic acid. By inhibiting this enzyme, trimethoprim disrupts the biosynthesis of nucleic acids and proteins in bacteria, leading to their growth inhibition. The drug has a significantly higher affinity for bacterial dihydrofolate reductase compared to the mammalian enzyme, ensuring selective antibacterial activity.

Pharmacodynamics

Trimethoprim exerts its antimicrobial effects by disrupting bacterial nucleic acid synthesis. It is effective against various gram-negative bacteria and some coagulase-negative Staphylococcus species. Resistance can develop through mechanisms such as alterations to the bacterial cell wall or overproduction of the target enzyme. Monitoring for potential blood disorders is important during therapy, as rare adverse effects can occur.

Pharmacokinetics

Trimethoprim is well absorbed from the gastrointestinal tract and reaches peak plasma concentrations within 1-4 hours post-administration. It has a volume of distribution that suggests extensive tissue penetration, including into the lungs and kidneys, and is primarily excreted unchanged in the urine. The elimination half-life is approximately 8-10 hours, and dosing adjustments may be necessary in cases of renal impairment.

Contra-indications

• Severe renal impairment
• Known hypersensitivity to trimethoprim or any component of the formulation

Adverse effects

• Diarrhoea
• Nausea
• Headache
• Dizziness
• Fatigue
• Skin reactions
• Vomiting
• Anxiety
• Agranulocytosis
• Eosinophilia
• Photosensitivity reactions
• Thrombocytopenia
• Leukopenia
• Pseudomembranous colitis

Interactions

• Increases exposure to pramipexole
• Increases exposure to treprostinil
• Increases exposure to dopaminergic receptor agonists
• Increases concentration of antiepileptics
• Increases concentration of fosphenytoin
• Increases concentration of phenytoin
• Increases risk of haematological toxicity with azathioprine in renal transplant patients
• Increases concentration of digoxin
• Increases exposure to repaglinide

Precautions

• Caution in patients with renal impairment
• Caution in elderly patients (75 years and over)
• Monitor for signs of blood disorders such as sore throat, fever, and pallor
• Consider local antimicrobial susceptibility patterns before use

Pregnancy

Manufacturer advises avoidance due to potential fetal developmental toxicity observed in animal studies.

Breast-feeding

Manufacturer advises avoidance as trimethoprim is present in milk in animal studies.

Storage

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

Formulations

• Tablets
• Oral suspension
• Injection solution

Indications

• Bacterial infections
• Toxoplasmosis in pregnancy (in combination with pyrimethamine and folinic acid)
• Congenital toxoplasmosis (in combination with pyrimethamine and folinic acid)

Dosage

Children: For children aged 12–17 years, the recommended dose is 1 g three times a day until delivery for toxoplasmosis in pregnancy. For other specific conditions, refer to the BNF for Children for detailed dosing guidelines.

Adults: For adults, the typical dosing for bacterial infections can vary, and it is essential to refer to the BNF for specific recommendations based on the condition being treated. Generally, dosage adjustments may be necessary in renal impairment.

Mechanism of action

Sulfadiazine acts as a competitive inhibitor of the bacterial enzyme dihydropteroate synthetase, blocking the conversion of para-aminobenzoic acid (PABA) to folic acid. This inhibition is crucial for bacterial growth and reproduction, as folic acid is vital for nucleic acid synthesis.

Pharmacodynamics

Sulfadiazine is a synthetic bacteriostatic antibiotic effective against many gram-positive and some gram-negative organisms. It inhibits bacterial multiplication by interfering with folic acid metabolism. Resistance to sulfadiazine usually implies resistance to all sulfonamides, as they share similar mechanisms of action.

Pharmacokinetics

Sulfadiazine is well absorbed when administered orally, with high tissue distribution. It achieves significant concentrations in various bodily fluids, including pleural and synovial fluids. While it is effective, its absorption can be affected by the presence of pus, which can inhibit its antibacterial action. Renal function can influence its clearance, necessitating dose adjustments in cases of impaired renal function.

Contra-indications

• Acute porphyrias

Adverse effects

• Agranulocytosis
• Aplastic anaemia
• Haemolytic anaemia
• Decreased appetite
• Ataxia
• Back pain
• Blood disorders
• Cough
• Crystaluria
• Cyanosis
• Depression
• Diarrhoea
• Dizziness
• Drowsiness
• Dyspnoea
• Eosinophilia
• Erythema nodosum
• Fatigue
• Fever
• Haematuria
• Hallucination
• Headache
• Hepatic disorders
• Hypoglycaemia
• Neutropenia
• Oral disorders
• Pancreatitis
• Photosensitivity reaction
• Skin reactions
• Thrombocytopenia
• Tinnitus
• Vertigo
• Vomiting

Interactions

• Sulfadiazine + antiepileptics: Moderate (increases concentration)
• Sulfadiazine + fosphenytoin: Moderate (increases concentration)
• Sulfadiazine + phenytoin: Moderate (increases concentration)

Precautions

• Caution in asthma
• Caution in blood disorders
• Caution in elderly patients
• Monitor blood counts on prolonged treatment
• Plasma concentration monitoring may be required in moderate to severe renal impairment

Pregnancy

Risk of neonatal haemolysis and methaemoglobinaemia in the third trimester; fear of increased risk of kernicterus in neonates appears to be unfounded.

Breast-feeding

Small risk of kernicterus in jaundiced infants and of haemolysis in G6PD-deficient infants.

Storage

Store in a cool, dry place away from light.

Formulations

• Solution for infusion
• Oral suspension

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

• 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.

Indications

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

Dosage

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

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

Mechanism of action

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

Pharmacodynamics

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

Pharmacokinetics

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

Adverse effects

• Bloating
• Diarrhea
• Abdominal pain
• Flatulence

Precautions

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

Pregnancy

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

Breast-feeding

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

Storage

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

Formulations

• Powder
• Granules
• Tablets
• Syrup

Indications

• Wound management
• Silicone implants
• Dermal fillers
• Medical lubricants
• Scar treatment

Dosage

Children: Refer to specific product guidelines for paediatric dosages, as silicone applications vary widely.

Adults: Refer to specific product guidelines for adult dosages, as silicone applications vary widely.

Mechanism of action

Silicones exhibit their effects primarily through their physical properties rather than a specific biochemical mechanism. They form a protective barrier that is hydrophobic, preventing moisture and microbial penetration, which aids in wound healing and reduces the risk of infection. Their flexibility and inertness also allow them to integrate well with biological tissues.

Pharmacodynamics

Silicones are generally inert and do not interact significantly with biological systems. They provide mechanical support, lubricate surfaces, and facilitate healing without eliciting a strong immune response. Their low toxicity and biocompatibility contribute to their favorable pharmacodynamic profile in medical applications.

Pharmacokinetics

Silicones are not absorbed by the body when used in medical applications. They remain at the site of application and do not undergo significant metabolism. Their elimination is largely through physical means, including degradation over time or removal during surgical procedures. The pharmacokinetic properties can vary depending on the specific silicone formulation and application.

Pregnancy

Silicone is generally considered safe for use during pregnancy as it is inert and non-toxic. However, specific products should be evaluated for safety.

Breast-feeding

Silicone is also considered safe during breastfeeding as it does not transfer into milk; however, care should be taken with specific formulations.

Storage

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

Indications

• Flavoring agent in food and beverages
• Aromatherapy for stress relief
• Potential antioxidant supplementation

Dosage

Children: Refer to specific product guidelines for appropriate dosing, as pediatric doses can differ significantly based on age and formulation.

Adults: Refer to specific product guidelines for appropriate dosing as it may vary based on the form (e.g., extract, powder) and intended use.

Mechanism of action

The primary active component of vanilla, vanillin, acts as an antioxidant by scavenging free radicals, which helps to mitigate oxidative stress. It may also engage in various metabolic pathways including the degradation of vanillin and vanillate, contributing to its bioavailability and therapeutic effects.

Pharmacodynamics

Vanilla exhibits several pharmacodynamic properties, including its ability to enhance flavor perception and stimulate appetite. The antioxidant properties of vanillin can reduce cellular damage and support overall health. Additionally, it may influence mood and cognition through its aromatic compounds, which have been associated with improved psychological well-being.

Pharmacokinetics

Vanilla is typically consumed orally and is absorbed in the gastrointestinal tract. The bioavailability of vanillin can vary based on the formulation and method of consumption. Once absorbed, vanillin is metabolized in the liver and excreted primarily through urine. The half-life and exact pharmacokinetic parameters of vanilla compounds can differ based on individual metabolism and the presence of other substances.

Pregnancy

Vanilla is generally considered safe during pregnancy when used in food amounts. However, high concentrations or extracts should be used cautiously.

Breast-feeding

Vanilla is likely safe during breastfeeding when used in food amounts, but should be used cautiously in higher concentrations.

Storage

Store in a cool, dry place away from direct sunlight. Keep tightly closed to maintain flavor and prevent contamination.

Formulations

• Vanilla extract
• Vanilla powder
• Vanilla bean

Mechanism of action

Sulfadiazine is a competitive inhibitor of the bacterial enzyme dihydropteroate synthetase. This enzyme is needed for the proper processing of para-aminobenzoic acid (PABA) which is essential for folic acid synthesis. The inhibited reaction is necessary in these organisms for the synthesis of folic acid.

Pharmacodynamics

Sulfadiazine is a sulfonamide antibiotic. The sulfonamides are synthetic bacteriostatic antibiotics with a wide spectrum against most gram-positive and many gram-negative organisms. However, many strains of an individual species may be resistant. Sulfonamides inhibit multiplication of bacteria by acting as competitive inhibitors of <i>p</i>-aminobenzoic acid in the folic acid metabolism cycle. Bacterial sensitivity is the same for the various sulfonamides, and resistance to one sulfonamide indicates resistance to all. Most sulfonamides are readily absorbed orally. However, parenteral administration is difficult, since the soluble sulfonamide salts are highly alkaline and irritating to the tissues. The sulfonamides are widely distributed throughout all tissues. High levels are achieved in pleural, peritoneal, synovial, and ocular fluids. Although these drugs are no longer used to treat meningitis, CSF levels are high in meningeal infections. Their antibacterial action is inhibited by pus.

Mechanism of action

Trimethoprim is a reversible inhibitor of dihydrofolate reductase, one of the principal enzymes catalyzing the formation of tetrahydrofolic acid (THF) from dihydrofolic acid (DHF). Tetrahydrofolic acid is necessary for the biosynthesis of bacterial nucleic acids and proteins and ultimately for continued bacterial survival - inhibiting its synthesis, then, results in bactericidal activity. Trimethoprim binds with a much stronger affinity to bacterial dihydrofolate reductase as compared to its mammalian counterpart, allowing trimethoprim to selectively interfere with bacterial biosynthetic processes. Trimethoprim is often given in combination with sulfamethoxazole, which inhibits the preceding step in bacterial protein synthesis - given together, sulfamethoxazole and trimethoprim inhibit two consecutive steps in the biosynthesis of bacterial nucleic acids and proteins. As a monotherapy trimethoprim is considered bacteriostatic, but in combination with sulfamethoxazole is thought to exert bactericidal activity. Trimethoprim is a bacteriostatic lipophilic weak base structurally related to pyrimethamine. It binds to and reversibly inhibits the bacterial enzyme dihydrofolate reductase, selectively blocking conversion of dihydrofolic acid to its functional form, tetrahydrofolic acid. This depletes folate, an essential cofactor in the biosynthesis of nucleic acids, resulting in interference with bacterial nucleic acid and protein production. Bacterial dihydrofolate reductase is approximately 50,000 to 60,000 times more tightly bound by trimethoprim than is the corresponding mammalian enzyme. To determine the incidence & severity of hyperkalemia during trimethoprim therapy, 30 consecutive patients with acquired immunodeficiency syndrome receiving high-dose (20 mg/kg/day) trimethoprim were studied; in addition, the mechanism of trimethoprim-induced hyperkalemia was investigated in rats. Trimethoprim increased serum potassium concn by 0.6 mmol/l despite normal adrenocortical function & glomerular filtration rate. Serum potassium levels >5 mmol/l were observed during trimethoprim treatment in 15 of 30 patients. In rats, iv trimethoprim inhibited renal potassium excretion by 40% & increased sodium excretion by 46%. It was concluded that trimethoprim blocks apical membrane sodium channels in the mammalian distal nephron. As a consequence, the transepithelial voltage is reduced & potassium secretion is inhibited. Decreased renal potassium excretion secondary to these direct effects on kidney tubules leads to hyperkalemia in a substantial number of patients being treated with trimethoprim-containing drugs.

Pharmacodynamics

Trimethoprim exerts its antimicrobial effects by inhibiting an essential step in the synthesis of bacterial nucleic acids and proteins. It has shown activity against several species of gram-negative bacteria, as well as coagulase-negative _Staphylococcus_ species. Resistance to trimethoprim may arise via a variety of mechanisms, including alterations to the bacterial cell wall, overproduction of dihydrofolate reductase, or production of resistant dihydrofolate reductase. Rarely, trimethoprim can precipitate the development of blood disorders (e.g. thrombocytopenia, leukopenia, etc.) which may be preceded by symptoms such as sore throat, fever, pallor, and or purpura - patients should be monitored closely for the development of these symptoms throught the course of therapy. As antimicrobial susceptibility patterns are geographically distinct, local antibiograms should be consulted to ensure adequate coverage of relevant pathogens prior to use.