MWAFYAZOLE

Indications

• Roundworm infections
• Hookworm infections
• Whipworm infections
• Pinworm infections
• Other helminth infections

Dosage

Children: Child 1 month–9 years: Initially 1 mg/kg daily in divided doses on the first day, then increased to 3 mg/kg daily in divided doses, dose to be increased gradually over 3 days. Child 10–17 years: Initially 1 mg/kg daily in divided doses on the first day, then increased to

Adults: 100 mg for 1 dose, if reinfection occurs, a second dose may be needed after 2 weeks.

Mechanism of action

Mebendazole causes degenerative alterations in the tegument and intestinal cells of the worm by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization into microtubules. This leads to impaired glucose uptake and depletion of glycogen stores in the parasites, resulting in decreased ATP production, immobilization, and eventual death of the helminths.

Pharmacodynamics

Mebendazole is a synthetic broad-spectrum anthelmintic. Its principal mode of action is through the inhibition of tubulin polymerization, which results in the loss of cytoplasmic microtubules. This action disrupts organelle movement and interferes with the normal physiological processes of helminths, effectively leading to their death.

Pharmacokinetics

Mebendazole is poorly absorbed from the gastrointestinal tract, which contributes to its effectiveness as an anthelmintic. After oral administration, the drug is primarily metabolized in the liver. Its low solubility limits absorption, but it can still exert its effects on the intestinal parasites present in the gastrointestinal tract. The drug's elimination half-life is variable, and it is not significantly distributed in body tissues.

Contra-indications

• Blood disorders

Adverse effects

• Abnormal sensation in eye
• Anaemia
• Appetite decreased
• Asthenia
• Asthma exacerbated
• Chest discomfort
• Coma
• Confusion
• Conjunctival haemorrhage
• Constipation
• Diarrhoea
• Difficulty standing
• Difficulty swallowing
• Dizziness
• Fever
• Gastrointestinal discomfort
• Headache
• Hepatitis
• Hypotension
• Joint disorders
• Leucopenia
• Lymphatic abnormalities
• Myalgia
• Nausea
• Oedema
• Pain
• Psychiatric disorder
• Seizure
• Severe cutaneous adverse reactions (SCARs)
• Stupor
• Tachycardia
• Tremor
• Urinary incontinence
• Vertigo
• Vomiting

Interactions

• Cimetidine (increases concentration of mebendazole)

Precautions

• Use with caution in patients with epilepsy
• Use with caution in patients with Sjögren’s syndrome

Pregnancy

Embryotoxic in animal studies, avoid if possible.

Breast-feeding

No information available.

Storage

Store in a cool, dry place away from light.

Formulations

• Chewable tablet 100 mg

Indications

• Dyspepsia
• Peptic ulcer disease
• Gastroesophageal reflux disease (GERD)
• Heartburn
• Diarrhea
• Mucosal irritations

Dosage

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

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

Mechanism of action

Aluminum acts as an astringent, causing local shrinkage or constriction of body tissues through osmotic flow of fluids away from the area of application. This mechanism assists in reducing mucous secretions and managing conditions such as peptic ulcers and diarrhea. Additionally, it can help in drying and hardening of tissues when applied topically.

Pharmacodynamics

Aluminum-based antacids work by neutralizing gastric acid, leading to an increase in gastric pH. This action helps to alleviate symptoms associated with excess gastric acid, such as heartburn and discomfort. The astringent properties of aluminum also contribute to its therapeutic effects in managing mucosal irritations and secretions.

Pharmacokinetics

Aluminum is absorbed minimally when taken orally, with a bioavailability of about 0.1 to 0.5%. The majority of aluminum is excreted renally, and its half-life can be prolonged in individuals with renal impairment. Long-term use may lead to accumulation and potential toxicity, particularly impacting bone and neurological health.

Interactions

• aluminiumhydroxide+deferasirox: Severe (decreases exposure)
• aluminiumhydroxide+enteralfeeds: Unknown (increases risk of blocked enteral or nasogastric tubes)
• aluminiumhydroxide+roxadustat: Unknown (decreases exposure)

Pregnancy

Aluminum compounds are generally considered safe in pregnancy when used as directed. However, excessive exposure should be avoided.

Breast-feeding

Aluminum is excreted in breast milk; caution is advised when administered to nursing mothers.

Storage

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

Formulations

• aluminium hydroxide suspension
• aluminium hydroxide tablets

Indications

• Support cardiovascular health
• Aid in digestion
• Provide quick energy
• Enhance nutrient intake
• Support muscle function

Dosage

Children: For children, bananas can be offered as a healthy snack or added to meals. There is no specific dosing, but one banana per day is a common recommendation.

Adults: There is no specific dosing for bananas, but including 1-2 bananas as part of a balanced diet can be beneficial.

Mechanism of action

The primary active components in bananas include potassium, which helps regulate fluid balance, muscle contractions, and nerve signals. The dietary fiber in bananas aids in digestion by promoting regular bowel movements and supporting gut health. Additionally, the antioxidants found in bananas may help reduce oxidative stress and inflammation in the body.

Pharmacodynamics

Bananas exhibit pharmacodynamic properties primarily through their nutrient content. The potassium in bananas plays a crucial role in maintaining normal blood pressure and heart function. The soluble fiber helps regulate blood sugar levels by slowing the absorption of sugar, while the presence of vitamins and antioxidants contributes to overall health and well-being.

Pharmacokinetics

Bananas are digested and absorbed in the gastrointestinal tract. The carbohydrates are broken down into sugars, which are then absorbed into the bloodstream. The potassium and other vitamins are also absorbed through the intestinal lining. The effects of consuming bananas can be seen relatively quickly, particularly in terms of energy provision due to their carbohydrate content.

Pregnancy

Bananas are generally considered safe to eat during pregnancy and can provide essential nutrients like potassium and vitamin B6.

Breast-feeding

Bananas are safe during breastfeeding, providing important vitamins and minerals.

Storage

Store bananas at room temperature. They can be kept in the refrigerator to slow ripening, but the skin may darken.

Indications

• Acidulant in food and beverages
• Preservative in pharmaceutical formulations
• pH adjuster in various chemical preparations

Dosage

Children: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Adults: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Mechanism of action

Citric acid acts by chelating metal ions, which can enhance the solubility of certain compounds and improve their bioavailability. It also contributes to the acidity of the environment, which can influence enzymatic activity and metabolic pathways, particularly in the degradation of citronellol.

Pharmacodynamics

Citric acid exhibits mild pharmacological effects primarily attributed to its role in metabolic processes. It aids in the regulation of pH levels, which can impact enzymatic reactions and biochemical pathways. The acid's chelating properties may help to reduce the toxicity of certain metal ions in biological systems.

Pharmacokinetics

Citric acid is rapidly absorbed after oral administration and is metabolized in the liver. It undergoes conversion to various metabolites in the citric acid cycle, contributing to energy production. The elimination primarily occurs through urine, with minimal accumulation in the body.

Pregnancy

Citric acid is generally regarded as safe during pregnancy when used in food amounts. However, consult a healthcare provider for advice on medicinal use.

Breast-feeding

Citric acid is considered safe during breastfeeding when consumed in food amounts. For medicinal use, consult a healthcare provider.

Storage

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

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

• Lead poisoning
• Mercury poisoning
• Calcium overload
• Certain diagnostic procedures involving heavy metals

Dosage

Children: Refer to the BNF for Children for appropriate dosing information tailored for paediatric patients.

Adults: Refer to the BNF for specific dosing guidelines based on the condition being treated, considering factors such as the severity of metal poisoning and renal function.

Mechanism of action

Edetate functions by forming stable complexes with divalent and trivalent metal ions, including lead and calcium, through its multiple carboxylate and amine groups. This chelation renders the metals more soluble and promotes their renal excretion, thereby reducing their toxic effects in the body.

Pharmacodynamics

The chelation of metals by edetate decreases the free metal concentration in the bloodstream, which mitigates the toxic effects associated with heavy metal accumulation. The efficacy of edetate in removing metals such as lead has been well documented, and its ability to bind calcium can influence calcium homeostasis in certain clinical scenarios.

Pharmacokinetics

Edetate is administered intravenously, with rapid distribution throughout the extracellular fluid. It is primarily excreted unchanged by the kidneys. The onset of action occurs quickly after administration, and the duration depends on the dose and the patient's renal function. The elimination half-life is approximately 1 hour but may vary based on renal clearance.

Contra-indications

• Hypersensitivity to edetate or any component of the formulation
• Severe renal impairment
• Active bleeding disorders

Adverse effects

• Hypocalcemia
• Nausea
• Vomiting
• Diarrhea
• Abdominal pain
• Headache
• Rash
• Fever

Interactions

• May enhance the effects of anticoagulants
• Concurrent use with calcium supplements may reduce effectiveness
• May interfere with the absorption of certain medications due to changes in gastrointestinal motility

Precautions

• Use with caution in patients with renal impairment
• Monitor electrolyte levels, particularly calcium, during treatment
• Assess the patient's hydration status before administration

Pregnancy

Limited data on the use of edetate in pregnancy. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Caution is advised as it is not known whether edetate is excreted in human milk. Weigh the risks and benefits before use.

Storage

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

Formulations

• Edetate disodium injection
• Edetate calcium disodium injection

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

Adults: Refer to specific guidelines for management of methyl mercaptan exposure, as there are no established therapeutic doses due to its toxicity.

Mechanism of action

Methyl mercaptan exerts its toxic effects primarily through the reversible inhibition of cytochrome c oxidase, similar to mechanisms observed in cyanide and hydrogen sulfide poisoning. It also inhibits brain sodium and potassium ATPase activity. These mechanisms contribute to its potential to induce coma and other neurological disturbances. Additionally, methyl mercaptan has been implicated in the pathogenesis of hepatic coma, indicating its impact on liver function and metabolism. The compound stabilizes erythrocyte membranes against hypotonic hemolysis at low concentrations, which may be linked to its anesthetic properties.

Pharmacodynamics

The pharmacodynamics of methyl mercaptan involve its ability to disrupt normal cellular respiratory processes and membrane stability. The inhibition of cytochrome c oxidase leads to impaired oxidative phosphorylation, causing cellular hypoxia. Furthermore, its effect on sodium and potassium ATPase can disrupt ionic balance within cells, potentially leading to cellular dysfunction and death. The compound's anesthetic-like effects differentiate it from common anesthetics, particularly in its toxicity profile, as it can elicit significant adverse reactions even at lower concentrations.

Pharmacokinetics

The pharmacokinetics of methyl mercaptan are not extensively characterized in clinical literature, but it is known to be rapidly absorbed through inhalation. Once in the body, it is likely metabolized by the liver, consistent with its involvement in hepatic coma. The gas is highly soluble in water and biological fluids, which may facilitate its distribution throughout tissues. Elimination pathways are not well defined, but it is presumed to be excreted through respiration and potentially other metabolic routes.

Pregnancy

There is limited information on the safety of methyl mercaptan in pregnancy. It is advisable to avoid exposure whenever possible due to potential risks.

Breast-feeding

The effects of methyl mercaptan during breastfeeding are not well studied. Caution is recommended due to the potential for unknown risks.

Storage

Store in a cool, dry place away from light and heat. Ensure containers are tightly sealed to prevent exposure and contamination.

Indications

• Allergic conditions
• Autoimmune diseases
• Asthma and chronic obstructive pulmonary disease (COPD)
• Certain cancers (e.g., leukemia, lymphoma)
• Skin conditions (e.g., dermatitis)
• Inflammatory bowel disease
• Multiple sclerosis exacerbations
• Severe infections requiring immunosuppression

Dosage

Children: Refer to BNF for Children for specific dosing; doses vary significantly based on the child's age, weight, and condition being treated.

Adults: Refer to BNF for specific dosing; typically, initial doses range from 4 to 48 mg depending on the severity of the condition.

Mechanism of action

Methylprednisolone exerts its effects by binding to glucocorticoid receptors, leading to the modulation of gene expression. This interaction influences the transcription of anti-inflammatory proteins while suppressing the expression of pro-inflammatory genes, ultimately resulting in reduced inflammation and immune response.

Pharmacodynamics

The pharmacodynamic effects of methylprednisolone are characterized by its ability to decrease inflammation, suppress the immune response, and affect carbohydrate metabolism. Therapeutic doses lead to various systemic effects, including modification of leukocyte distribution and inhibition of cytokine production.

Pharmacokinetics

Methylprednisolone is well absorbed after oral administration, with a bioavailability of approximately 50%. It has a volume of distribution that reflects extensive tissue binding. The drug is metabolized primarily in the liver through conjugation and reduction, and its metabolites are excreted in urine. The half-life varies based on the route of administration but is generally around 18 to 36 hours.

Adverse effects

• Increased blood pressure
• Hyperglycemia
• Weight gain
• Mood changes
• Insomnia
• Gastrointestinal disturbances
• Increased susceptibility to infections

Interactions

• methylphenidate+apraclonidine: Severe (decreases effects)
• methylthioninium chloride+bupropion: Severe (increases risk of severe hypertension)
• methylphenidate+linezolid: Severe (increases risk of elevated blood pressure)
• rasagiline+methylphenidate: Severe (increases risk of a hypertensive crisis)
• mao-inhibitors+methylphenidate: Severe (increases risk of a hypertensive crisis)
• dronedarone+methylprednisolone: Moderate (increases exposure)
• miconazole+methylprednisolone: Moderate (increases concentration)
• antifungals, azoles+methylprednisolone: Moderate (increases exposure)
• crizotinib+methylprednisolone: Moderate (increases exposure)

Precautions

• Use with caution in patients with hypertension
• Monitor blood glucose levels in diabetic patients
• Consider potential for infection risk due to immunosuppression
• Evaluate for psychiatric effects in susceptible individuals

Pregnancy

Corticosteroids may be used during pregnancy if the potential benefit justifies the risk to the fetus. Careful monitoring is advised.

Breast-feeding

Corticosteroids are excreted in breast milk; caution is advised. Monitor the infant for potential effects.

Storage

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

Formulations

• Tablets
• Injectable solutions
• Topical preparations

Mechanism of action

Methylsulphate functions as a methylating agent, transferring a methyl group to nucleophiles. This process involves the formation of a sulfonium ion, which is highly reactive and can readily react with nucleophilic sites on various substrates, leading to methylation reactions.

Pharmacodynamics

The pharmacodynamics of methylsulphate is primarily related to its role as a methylating agent in biochemical reactions. It can alter the structure and function of biological molecules, potentially affecting cellular processes and signaling pathways. However, detailed pharmacodynamic studies specific to therapeutic use are limited.

Pharmacokinetics

There is limited information on the pharmacokinetics of methylsulphate, given its typical use as a reagent in laboratory settings rather than a clinical drug. When used in chemical reactions, its reactivity and transformation into other compounds would dictate its pharmacokinetic profile, which could vary significantly based on the specific context of use.

Pregnancy

There is limited data on the use of methylsulphate in pregnancy. Consult relevant guidelines.

Breast-feeding

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

Storage

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

Indications

• Preservative in cosmetics
• Preservative in pharmaceuticals
• Preservative in food products

Dosage

Children: Refer to specific product guidelines as dosing varies based on formulation and concentration used.

Adults: Refer to specific product guidelines as dosing varies based on formulation and concentration used.

Mechanism of action

Parabens work by inhibiting the growth of microorganisms through their ability to disrupt the cellular processes of bacteria and fungi. They penetrate the microbial cell membrane and disrupt enzyme and protein functions, leading to cell death. Parabens are known to have low toxicity and are metabolized by the body, subsequently being excreted in urine.

Pharmacodynamics

Parabens demonstrate broad-spectrum antimicrobial activity, making them effective preservatives in various formulations. Their efficacy is influenced by factors such as concentration, pH, and the presence of other ingredients in the formulation. Due to their structural similarity to estrogen, there has been concern regarding their potential endocrine-disrupting effects, although the clinical significance of this is still debated.

Pharmacokinetics

Parabens are readily absorbed through the skin and gastrointestinal tract. Once absorbed, they are rapidly metabolized primarily in the liver. They undergo hydrolysis to form para-hydroxybenzoic acid, which is then conjugated with glucuronic acid and excreted in urine. The half-life of parabens in the human body is relatively short, and they are eliminated rapidly.

Adverse effects

• Allergic reactions, such as skin rashes
• Irritation at the site of application
• Endocrine disruption (in high concentrations)

Precautions

• Use with caution in individuals with known sensitivities or allergies to parabens
• Consider potential endocrine effects with prolonged exposure

Pregnancy

Parabens are generally considered safe in cosmetics and personal care products during pregnancy, although caution is advised due to potential endocrine disruption.

Breast-feeding

Parabens are considered safe in breastfeeding, but it is recommended to use products with minimal or no parabens when possible.

Storage

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

Formulations

• Topical creams
• Lotions
• Shampoos
• Conditioners
• Makeup products
• Pharmaceutical preparations

Indications

• Hyperthyroidism
• Graves' disease
• Thyroid storm

Dosage

Children: Refer to the BNF

Adults: The usual initial dose of propylthiouracil in adults is 300 mg per day, divided into 3 doses. The maintenance dose is typically 100-150 mg per day, adjusted based on thyroid function tests.

Mechanism of action

Propylthiouracil acts by inhibiting the enzyme thyroid peroxidase, which is involved in the iodination of tyrosine residues in thyroglobulin, a precursor of thyroid hormones. By blocking this enzyme, PTU reduces the production of thyroxine (T4) and triiodothyronine (T3), leading to decreased thyroid hormone levels in circulation. Additionally, PTU inhibits the conversion of T4 to T3 in peripheral tissues, further contributing to its antithyroid effects.

Pharmacodynamics

The pharmacodynamic effects of propylthiouracil are primarily centered around its ability to lower thyroid hormone levels, which helps alleviate symptoms of hyperthyroidism such as increased heart rate, weight loss, and anxiety. The onset of action can vary, but therapeutic effects may be observed within several weeks of initiation. Monitoring thyroid function tests is essential to assess the efficacy and adjust dosing as needed.

Pharmacokinetics

Propylthiouracil is well absorbed from the gastrointestinal tract, though its bioavailability can be affected by factors such as food intake. The drug is extensively metabolized in the liver, and its elimination half-life averages around 1-2 hours. Most of the drug is excreted in urine as metabolites. It is important to note that due to its rapid metabolism, multiple daily doses may be required to maintain therapeutic levels.

Interactions

• propylthiouracil+metyrapone: Severe (decreases effects)

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

• Diarrhea
• Gastrointestinal infections
• Toxin elimination

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines as they are dependent on the formulation and condition being treated.

Adults: Refer to the BNF for specific dosing guidelines as they are dependent on the formulation and condition being treated.

Mechanism of action

Silicates function by adsorbing toxins and pathogens in the gastrointestinal tract, thereby reducing their absorption into the systemic circulation. This mechanism is particularly beneficial in conditions such as diarrhea or gastrointestinal infections, where the reduction of harmful substances can help alleviate symptoms.

Pharmacodynamics

The pharmacodynamics of silicates are characterized by their ability to bind with various substances in the gut, including toxins, bacteria, and other pathogens. This binding helps in reducing the irritative effects of these substances on the intestinal lining and can assist in normalizing bowel function.

Pharmacokinetics

Silicates are generally not absorbed systemically after oral administration. They act locally within the gastrointestinal tract, where they exert their effects. Due to their physical properties, they can remain in the gut for prolonged periods, enhancing their efficacy in adsorbing harmful agents.

Pregnancy

There is limited data on the use of silicates during pregnancy. It is advisable to avoid use unless clearly needed.

Breast-feeding

Silicates are not known to be excreted in human milk. Caution is advised when using.

Storage

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

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

• Constipation
• Diagnostic aid in colonoscopy preparation
• Management of hyperosmolality in various conditions

Dosage

Children: For children, the dosage should be determined based on age and condition, and it is advised to refer to the BNF for Children for specific dosing guidelines.

Adults: The typical dose for adults is 30 to 150 mL of sorbitol solution (70%) taken orally, as needed, usually before bedtime.

Mechanism of action

Sorbitol exerts its laxative effect by drawing water into the large intestine, thereby stimulating bowel movements. It acts as a hygroscopic agent, pulling water from tissues into the feces, which reflexively stimulates evacuation. In metabolic pathways, sorbitol is produced from glucose via aldose reductase and is converted to fructose by sorbitol dehydrogenase, with implications in diabetic complications such as retinopathy.

Pharmacodynamics

Sorbitol's laxative effect results from its osmotic properties, which increase the water content of the stool and soften it, facilitating easier passage. Additionally, sorbitol can induce apoptosis in certain cancer cell lines, indicating potential therapeutic implications beyond its laxative use. The modulation of intracellular signaling pathways through the regulation of proteins such as Bax and Bcl-2 suggests a complex role in cellular health and disease.

Pharmacokinetics

Sorbitol is poorly absorbed in the gastrointestinal tract, which contributes to its efficacy as a laxative. It is metabolized in the liver, primarily through the polyol pathway. The absorption and distribution of sorbitol are affected by its osmotic properties, leading to increased intestinal water retention. Its elimination is primarily via renal excretion, with minimal systemic absorption, thus reducing the risk of systemic side effects.

Adverse effects

• Diarrhea
• Abdominal cramps
• Nausea
• Vomiting
• Electrolyte imbalances

Precautions

• Use with caution in patients with renal impairment
• May exacerbate gastrointestinal conditions

Pregnancy

Sorbitol is generally considered safe during pregnancy, but should be used under medical supervision.

Breast-feeding

Sorbitol is excreted in breast milk in small amounts; consult a healthcare provider before use.

Storage

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

Formulations

• Oral solution
• Syrup

Indications

• Sweetening agent in food and beverages
• Ingredient in pharmaceutical formulations
• Source of quick energy

Dosage

Children: Refer to specific formulations and clinical guidelines for dosing, as sucrose does not have a standardized dosage. Typically used as needed for sweetening.

Adults: Refer to specific formulations and clinical guidelines for dosing, as sucrose does not have a standardized dosage. Typically used as needed for sweetening.

Mechanism of action

Sucrose is metabolized in the body to glucose and fructose, which are then used as energy sources. It does not have a specific pharmacological mechanism of action but contributes to energy metabolism via the glycolytic and citric acid pathways.

Pharmacodynamics

Upon ingestion, sucrose is hydrolyzed by the enzyme sucrase into its constituent monosaccharides, glucose and fructose. These monosaccharides are absorbed in the small intestine and enter the bloodstream, leading to a rise in blood glucose levels. This process provides a quick source of energy for cellular functions.

Pharmacokinetics

Sucrose is rapidly absorbed in the gastrointestinal tract after hydrolysis. Its absorption depends on the presence of sucrase in the intestine. Once in the bloodstream, glucose can be utilized by cells or stored as glycogen in the liver and muscles. The elimination half-life of sucrose itself is not well-defined as it is quickly broken down and utilized.

Pregnancy

Sucrose is generally regarded as safe during pregnancy when consumed in moderation as part of a balanced diet.

Breast-feeding

Sucrose is considered safe during breastfeeding when consumed in normal dietary amounts.

Storage

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

Formulations

• Oral solution
• Granules
• Tablets

Indications

• Used as a thickening agent in food products
• Utilized in pharmaceutical formulations as a stabilizer
• Employed in cosmetics for texture improvement
• Applied in industrial products for its viscosity properties

Dosage

Children: Refer to specific product guidelines for appropriate use. Xanthan is used in formulations as a thickener or stabilizer, and dosage should be evaluated based on the specific product and formulation.

Adults: Refer to specific product guidelines for appropriate use. Xanthan is typically used in small quantities as a thickener or stabilizer in food and pharmaceutical products.

Mechanism of action

Xanthan functions primarily as a thickener and stabilizer. It acts by interacting with water molecules to form a gel-like consistency, which enhances the texture and stability of products. Its unique rheological properties allow it to maintain viscosity under varying conditions, which is beneficial in food and pharmaceutical applications.

Pharmacodynamics

Xanthan's action is primarily physical rather than pharmacological. It does not exert a direct therapeutic effect but influences the delivery and stability of active ingredients in formulations. The gel formation and viscosity changes help ensure the uniform distribution of substances in liquid formulations, which can improve the effectiveness of the drug delivery.

Pharmacokinetics

As xanthan is a polysaccharide, it is not absorbed in the gastrointestinal tract when ingested. It passes through the digestive system largely unchanged. In terms of metabolism, xanthan is broken down by colonic bacteria, resulting in short-chain fatty acids. Its pharmacokinetic profile indicates that it has a low bioavailability due to its large molecular size and structure.

Pregnancy

There is insufficient data on the use of xanthan during pregnancy. Consult a healthcare professional before use.

Breast-feeding

There is insufficient data on the excretion of xanthan in human milk. Consult a healthcare professional before use.

Storage

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

Formulations

• Xanthan gum powder

Mechanism of action

Mebendazole causes degenerative alterations in the tegument and intestinal cells of the worm by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly into microtubules. The loss of the cytoplasmic microtubules leads to impaired uptake of glucose by the larval and adult stages of the susceptible parasites, and depletes their glycogen stores. Degenerative changes in the endoplasmic reticulum, the mitochondria of the germinal layer, and the subsequent release of lysosomes result in decreased production of adenosine triphosphate (ATP), which is the energy required for the survival of the helminth. Due to diminished energy production, the parasite is immobilized and eventually dies. Although the exact mechanism of anthelmintic activity of mebendazole has not been fully elucidated, the drug appears to cause selective and irreversible inhibition of the uptake of glucose and other low molecular weight nutrients in susceptible helminths; inhibition of glucose uptake appears to result in endogenous depletion of glycogen stores in the helminth. Mebendazole does not inhibit glucose uptake in mammals. Mebendazole appears to cause degenerative changes in the intestine of nematodes and in the absorptive cells of cestodes. The principal anthelmintic effect of the drug appears to be degeneration of cytoplasmic microtubules within these intestinal and absorptive cells. Microtubular deterioration results in inhibition of organelle movement and interferes with the absorptive and secretory function. As a result of excessive accumulation of intracellular transport secretory granules, hydrolytic and proteolytic enzymes are released and cause cellular autolysis. This irreversible damage leads to death of the parasite. Vermicidal; may also be ovicidal for ova or most helminths; mebendazole causes degeneration of parasite's cytoplasmic microtubules and thereby selectively and irreversibly blocks glucose uptake in susceptible adult intestine-dwelling helminths and their tissue-dwelling larvae; inhibition of glucose uptake apparently results in depletion of the parasite's glycogen stores; this, in turn, results in reduced formation of adenosine triphosphate (ATP) required for survival and reproduction of the helminth; corresponding energy levels are gradually reduced until death of the parasite ensues; mebendazole does not appear to affect serum glucose concentrations in humans, however. Benzimidazoles produce many biochemical changes in susceptible nematodes, eg, inhibition of mitochondrial fumarate reductase, reduced glucose transport, and uncoupling of oxidative phosphorylation ... /but/ the primary action ... /should be/ to inhibit microtubule polymerization by binding to beta-tubulin. The selective toxicity of these agents derives from the fact that specific, high-affinity binding to parasite beta-tubulin occurs at much lower concn than does binding to the mammalian protein ... Benzimidazole-resistant Haemonchus contortus display reduced high-affinity drug binding to beta-tubulin and alterations in beta-tubulin isotype gene expression that correlate with drug resistance ... Two identified mechanisms of drug resistance in nematodes involve both a progressive loss of "susceptible" beta-tubulin gene isotypes together with emergence of a "resistant" isotype with a conserved point mutation that encodes a tyrosine instead of phenylalanine at position 200 of beta-tubulin. While this mutation may not be required for benzimidazole resistance in all parasites, eg, Giardia lamblia, benzimidazole resistance in parasitic nematodes is unlikely to be overcome by novel benzimidazole analogs, because tyrosine also is present at position 200 of human beta-tubulin. /Benzimidazoles/

Pharmacodynamics

Mebendazole is a (synthetic) broad-spectrum anthelmintic. The principal mode of action for Mebendazole is by its inhibitory effect on tubulin polymerization which results in the loss of cytoplasmic microtubules.

Mechanism of action

Aluminum Acetate is an astringent. An astrignent is a chemical that tends to shrink or constrict body tissues, usually locally after topical medicinal application. The shrinkage or constriction is through osmotic flow of water (or other fluids) away from the area where the astringent was applied. Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions. This can happen with a sore throat, hemorrhages, diarrhea, or with peptic ulcers. Externally applied astringents, which cause mild coagulation of skin proteins, dry, harden, and protect the skin. Acne sufferers are often advised to use astringents if they have oily skin. Astringents also help heal stretch marks and other scars. Mild astringent solutions are used in the relief of such minor skin irritations as those resulting from superficial cuts, allergies, insect bites, or fungal infections such as athlete's foot. Excessive dietary aluminum has been proposed to be a factor contributing to several neurological disorders in humans. Six 8-week-old female Swiss Webster mice were fed for 10 wk purified diets containing 100 (control), 500 or 1000 ug aluminum/g diet. Brain and liver lipid peroxidation was determined by evaluating the production of 2-thiobarbituric acid reactive substances in brain and liver homogenates in the presence or absence of 50 uM ferrous iron. 2-Thiobarbituric acid reactive substances production in the absence of iron in brain homogenates from mice fed the 1000 ug/g diet was higher (30%) than that in the 100 ug/g control group (3.1 vs 2.4 nmol 2-thiobarbituric acid reactive substances/mg protein). The addition of ferrous iron increased 2-thiobarbituric acid reactive substances production in brain homogenates from all 3 dietary groups. The iron induced 2-thiobarbituric acid reactive substances production was 26% higher in the 1000 ug/g brain homogenates than in the 100 ug/g group (4.9 vs 3.9 nmol 2-thiobarbituric acid reactive substances/mg protein). Brain 2-thiobarbituric acid reactive substances production in the presence and absence of iron was similar between the 100 and 500 ug/g aluminum groups. 2-Thiobarbituric acid reactive substances production in liver homogenates measured either with or without iron was similar for the 3 groups. These results show that, in mice, dietary aluminum intoxication leads to increased brain 2-thiobarbituric acid reactive substance production, suggesting that enhanced lipid peroxidation may be one possible mechanism underlying the neurological damage associated with increased tissue aluminum. Evidence is presented indicating that dementias are associated with a relative insufficiency of magnesium in the brain. Such insufficiency may be attributable to low intake or retention of magnesium; high intake of a neurotoxic metal, such as aluminum, which inhibits activity of magnesium requiring enzymes; or impaired transport of magnesium and/or enhanced transport of the neurotoxic metal into brain tissue. It is proposed that Alzheimer's disease involves a defective transport process, characterized by both an abnormally high incorporation of aluminum and an abnormally low incorporation that an altered serum protein contributes to the progression of Alzheimer's disease by having a greater affinity for aluminum than for magnesium, in contrast to the normal protein, which binds magnesium better than aluminum. The altered protein crosses the blood-brain barrier more efficiently than the normal protein and competes with the normal protein in binding to brain neurons. Binding of the altered protein to the target neurons would both facilitate aluminum uptake and impede magnesium uptake. Evidence suggests that albumin is the serum protein that is altered. Aluminum is established as a neurotoxin, although the basis for its toxicity is unknown. It recently has been shown to alter the function of the blood-brain barrier, which regulates ex

Mechanism of action

... The primary mechanisms by which methyl mercaptan has caused death and induces coma appear to reside with its reversible inhibition of cytochrome c oxidase (as in cyanide and hydrogen sulfide poisoning) and its inhibition of brain sodium and potassium ATPase activity. Methanethiol (CH3SH) has been implicated in the pathogenesis of hepatic coma. Studies are presented to identify the possible biochemical basis of anesthesia-like effects of methanethiol and those features, which distinguish such effects from common anesthetics and may represent the basis of its toxicity. CH3SH was found to stabilize erythrocyte membranes against hypotonic hemolysis at relatively low concentrations. At 37 degrees C the AH25 value for human erythrocyte antihemolysis was observed at a concentration of 0.34 mumol of CH3SH bound per mg of erythrocyte protein. Similar results were obtained with rat erythrocytes. This property of CH3SH is in common with other anesthetic agents. Anesthetic agents also inhibit the membrane-associated Na+, K+-adenosine triphosphatase (ATPase); however, for effective and nontoxic agents of this type the inhibition of ATPase activity is elicited at concentrations which are at least an order of magnitude higher than those which influence the membrane stability characterized by the antihemolysis effect. CH3SH was also found to inhibit the membrane Na+,K+-ATPase activity. The I25 value for the inhibition of human erythrocyte ATPase activity was obtained at CH3SH concentration of 0.12 mM which corresponded to 0.3 umol of CH3SH bound per mg of erythrocyte membrane protein. Rat erythrocyte membrane ATPase was somewhat more sensitive to CH3SH. In all cases, the binding of CH3SH to erythrocytes occurred primarily on the membrane. These results indicate that no differential exists with respect to the dose-response of these two activities associated with human erythrocyte membrane. Pulpal disease is intimately associated with the immune system's response to bacteria products. Clinical pathology is mediated in part by the production of pyrogenic cytokines, especially interleukin (IL)-1, tumor necrosis factor (TNF)-alpha, and IL-6. Methyl mercaptan (CH3SH), a volatile sulfur compound produced by anaerobic Gram-negative bacteria, has been shown to contribute to the production of IL-1 by human mononuclear cells. In this report, /the authors/ investigated the production of IL-1, TNF-alpha, and IL-6 by human pulp fibroblasts when stimulated for various periods of time with lipopolysaccharide (LPS) with or without the presence of CH3SH. We found that LPS and CH3SH had no effect on the production of IL-1 or TNF-alpha. However, LPS stimulated IL-6 production, and this production was augmented when CH3SH was present. /It was concluded/ that the volatile sulfur compound CH3SH plays a role in activation and modulation of the immune response through its role in production of IL-6. Hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) are the volatile sulfur compounds (VSC) that were investigated for a possible role in the etiology of periodontal disease. The results show that the permeability of porcine non-keratinized sublingual mucosa is increased by up to 75% or 103% following exposure to H2S and CH3SH, respectively. The effect may be attributed to VSC reaction with tissue components resulting in alteration in the integrity of the tissue barrier. The increase in permeability of the mucosa to (35)S-Na2SO4 was dependent on both the time of exposure and concentration of VSC in the head-space. The (35)S-H2S was retained by the mucosal tissue and was able to penetrate the intact layers consisting of non-keratinized epithelium, basal membrane, and connective tissue. Treatment of the mucosa with 0.22% ZnCl2, either prior to or after exposure to CH3SH, nullified the effect of CH3SH and restored the permeability to a state similar to that observed in control 95% air/5% CO2 systems. For more Mechanism of Action (Complete) data for METHYL MERCAPTAN (10 t

Mechanism of action

Sorbitol exerts its laxative effect by drawing water into the large intestine, thereby stimulating bowel movements. ... Sorbitol exerts hygroscopic and/or local irritant action, drawing water from tissues into feces and reflexly stimulating evacuation. The polyol pathway consists of two enzymes aldose reductase (AR) and sorbitol dehydrogenase (SDH); the former is the first enzyme in the polyol pathway, that catalyzes the reduction of glucose to sorbitol, the latter is the second one, that converts sorbitol to fructose using by NAD(+) as a cofactor. ... SDH activity, the second step in the polyol pathway, might make a greater contribution to the etiology of diabetic retinopathy than does the first step involving AR. /This paper proposes/ a novel hypothesis that polymorphisms of SDH gene may be correlated with SDH gene expression levels in diabetic retinas, thus being a valuable genetic marker for diabetic retinopathy. It has been reported that sorbitol induces apoptosis in several cancer cell lines. ... In /this/ study, the intracellular signaling pathways of sorbitol-induced apoptosis in human K562 cells were investigated using both morphological analysis and DNA fragmentation technique. In this study, we demonstrated that sorbitol-induced apoptosis in human K562 cells is a concentration- and time-dependent manner. This sorbitol-induced apoptosis in human K562 cells was also accompanied by the up-regulation of Bax, and down-regulation of p-Bcl-2, but no effect on the levels of Bcl-X(L). Moreover, the sorbitol treatment resulted in a significant reduction of mitochondria membrane potential, increase in the release of mitochondrial cytochrome c (cyt c), and activation of caspase 3. Furthermore, treatment with caspase 3 inhibitor (z-DEVD-fmk) was capable of preventing the sorbitol-induced caspase 3 activity and cell death. These results clearly demonstrate that the induction of apoptosis by sorbitol involves multiple cellular/molecular pathways and strongly suggest that pro- and anti-apoptotic Bcl-2 family proteins, mitochondrial membrane potential, mitochondrial cyt c, and caspase 3, they all participate in sorbitol-induced apoptotic process in human K562 cells. Chronic diabetic complications, in particular, nephropathy, peripheral and autonomic neuropathy, "diabetic foot," retinopathy, and cardiovascular disease, remain the major cause of morbidity and mortality in patients with diabetes mellitus. Growing evidence indicates that both increased activity of the sorbitol pathway of glucose metabolism and enhanced oxidative stress are the leading factors in the pathogenesis of diabetic complications. The relation between the two mechanisms remains the area of controversy. One group has reported that increased sorbitol pathway activity has a protective rather than detrimental role in complication-prone tissues because the pathway detoxifies toxic lipid peroxidation products. Others put forward a so-called "unifying hypothesis" suggesting that activation of several major pathways implicated in diabetic complications (eg, sorbitol pathway) occurs due to increased production of superoxide anion radicals in mitochondria and resulting poly(ADP-ribose) polymerase activation. This review (a) presents findings supporting a key role for the sorbitol pathway in oxidative stress and oxidative stress-initiated downstream mechanisms of diabetic complications, and (b) summarizes experimental evidence against a detoxifying role of the sorbitol pathway, as well as the "unifying concept."