RELAXYL OINTMENT

Dosage

Children: Refer to specific drug information for detailed dosage recommendations.

Adults: Refer to specific drug information for detailed dosage recommendations.

Mechanism of action

The mechanism of action varies depending on the specific drug that 'contains' certain active ingredients. Each compound will have its own unique pharmacological pathway and target within the body, which can include receptor modulation, enzyme inhibition, or other biochemical interactions.

Pharmacodynamics

Pharmacodynamics will depend on the active ingredients in the formulation. It generally encompasses the biochemical and physiological effects of the drug and its mechanisms of action, including the relationship between drug concentration and effect.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion of the specific active ingredients within the formulation. This can vary significantly based on the drug's chemical properties, route of administration, and individual patient factors.

Pregnancy

Consult with a healthcare provider before use, as safety during pregnancy has not been established.

Breast-feeding

Consult with a healthcare provider before use, as it is not known if this drug is excreted in human milk.

Storage

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

Indications

• Neuropathic pain
• Osteoarthritis
• Rheumatoid arthritis
• Postherpetic neuralgia
• Muscle pain

Dosage

Children: Refer to the specific product guidelines for dosage recommendations.

Adults: Refer to the specific product guidelines for dosage recommendations.

Mechanism of action

Capsaicin works by binding to the TRPV1 receptor, a transient receptor potential cation channel. This leads to the depolarization of sensory neurons and the release of substance P, a neuropeptide associated with pain perception. When capsaicin is applied repeatedly, it depletes substance P from nerve endings, resulting in a reduction of pain sensation over time.

Pharmacodynamics

The pharmacodynamics of capsaicin involve its ability to induce a burning sensation followed by a prolonged analgesic effect due to its action on the TRPV1 receptor. This receptor is involved in the detection and regulation of body temperature and pain. The initial stimulation of the receptor can lead to a transient increase in pain, but chronic exposure results in decreased sensitivity and pain relief.

Pharmacokinetics

Capsaicin is absorbed through the skin when applied topically, with systemic absorption being minimal. Its metabolism occurs in the liver, primarily via cytochrome P450 enzymes. The elimination half-life of capsaicin is not well documented, but it is generally excreted in urine as metabolites. Its pharmacokinetic properties vary based on the formulation used (cream, patch, etc.) and the site of application.

Adverse effects

• Skin irritation
• Burning sensation
• Redness
• Allergic reactions

Precautions

• Avoid contact with eyes and mucous membranes
• Use with caution in patients with sensitive skin
• Not recommended for use on broken skin

Pregnancy

Capsicum should be used with caution during pregnancy. Consult a healthcare professional before use.

Breast-feeding

Capsicum is generally considered safe but should be used with caution. Consult a healthcare professional before use.

Storage

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

Formulations

• Topical cream
• Ointment
• Plaster
• Capsules

Indications

• Dry skin conditions
• Atopic dermatitis
• Psoriasis
• Irritant contact dermatitis
• Eczema
• Skin barrier repair

Dosage

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

Adults: Apply a sufficient amount to the affected area as needed, ensuring even coverage. Frequency of application depends on the severity of the condition and the specific product used.

Mechanism of action

Greasy agents work primarily by forming a hydrophobic layer on the skin, which reduces transepidermal water loss. This occlusive effect retains moisture within the stratum corneum and enhances the skin's hydration levels. Additionally, they may facilitate the penetration of active ingredients in topical formulations by creating a conducive environment for absorption.

Pharmacodynamics

The pharmacodynamic properties of greasy agents involve their ability to alter the skin's hydration status and barrier function. They enhance the viscosity and spreadability of topical formulations, leading to prolonged skin contact time. This can improve the efficacy of co-administered active ingredients by maintaining skin moisture and reducing irritation, thus enhancing patient compliance with topical therapies.

Pharmacokinetics

Greasy agents are generally not systemically absorbed when applied topically; their pharmacokinetics are primarily localized to the site of application. The absorption of any active ingredients included in greasy formulations depends on the formulation's composition, the molecular size of the active agents, and the integrity of the skin barrier. The duration of action is influenced by the thickness of the applied layer and the formulation's occlusiveness.

Pregnancy

Greasy substances, often used for topical applications, generally do not have established safety profiles in pregnancy. Consult healthcare professionals for specific applications.

Breast-feeding

Safety during breastfeeding is not well established for greasy substances. Consult healthcare professionals before use.

Storage

Store in a cool, dry place away from direct sunlight. Ensure containers are tightly sealed to prevent contamination.

Indications

• Muscle spasms
• Musculoskeletal pain
• Spasticity

Dosage

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

Adults: Refer to the BNF for specific dosing information.

Mechanism of action

The exact mechanism of action of mephenesin is not fully understood. However, it has been observed to block both inward sodium and inward calcium currents in neurons. This action leads to a physiological effect that opposes the action of strychnine.

Pharmacodynamics

Mephenesin reduces neuronal excitability, which results in decreases in action potentials to muscle fibers. This ultimately leads to a reduction in spasticity, providing relief from muscle tension and spasms.

Pharmacokinetics

Mephenesin is absorbed from the gastrointestinal tract and reaches peak plasma concentrations within a few hours. It is metabolized in the liver and has an elimination half-life that allows for dosing several times a day. The drug is excreted primarily in urine, with both intact drug and metabolites present.

Pregnancy

There are no adequate and well-controlled studies in pregnant women. Use only if clearly needed.

Breast-feeding

Caution should be exercised when mephenesin is administered to a nursing mother.

Storage

Store at room temperature, away from moisture and heat.

Formulations

• Tablets
• Oral suspension

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

• Pellagra
• Hyperlipidaemia
• Nicotinic acid deficiency
• As a dietary supplement

Dosage

Children: Refer to BNF for Children for paediatric dosing information.

Adults: Refer to BNF for specific adult dosing guidelines.

Mechanism of action

Nicotinate functions primarily as a precursor to nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which are essential for various enzymatic reactions, including those involved in energy metabolism and DNA repair. It is involved in multiple biosynthetic pathways including nicotine biosynthesis and pyridine nucleotide cycling.

Pharmacodynamics

Nicotinate's pharmacodynamic properties are attributed to its role in redox reactions as a coenzyme. It enhances the activity of dehydrogenases and participates in the synthesis of fatty acids and cholesterol, influencing lipid metabolism. Additionally, it has vasodilatory effects, possibly due to its ability to release prostaglandins, which can lead to improved blood flow.

Pharmacokinetics

Nicotinate is well absorbed from the gastrointestinal tract. It is extensively metabolized in the liver, where it is converted into its active form, NAD. The elimination half-life varies but is generally around 20 to 45 minutes. Renal excretion plays a significant role in the elimination of nicotinate and its metabolites.

Pregnancy

There is limited information available on the safety of nicotinate during pregnancy. Consult healthcare professionals for specific guidance.

Breast-feeding

Limited data on the excretion of nicotinate in breast milk. Consult healthcare professionals for advice.

Storage

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

Indications

• Antimicrobial treatment
• Antioxidant therapy
• Flavoring agent in food
• Natural preservative
• Traditional medicine applications

Dosage

Children: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing.

Adults: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing.

Mechanism of action

The mechanism of action of oleoresin varies depending on its source and the specific compounds it contains. Generally, oleoresins exhibit antimicrobial activity, which may involve the disruption of microbial cell membranes or interference with metabolic processes. Additionally, some components may have anti-inflammatory and antioxidant effects, contributing to their therapeutic potential.

Pharmacodynamics

Oleoresins exhibit a range of pharmacodynamic effects, including antimicrobial, antioxidant, and anti-inflammatory activities. The specific effects will depend on the source of the oleoresin and its chemical composition. These properties are attributed to the various phytochemicals present, such as terpenes, phenolics, and other bioactive compounds, which can modulate biological pathways and influence physiological responses.

Pharmacokinetics

The pharmacokinetics of oleoresin are not well-defined due to the complexity of its composition. Generally, the absorption and metabolism of oleoresins can vary widely based on the individual compounds they contain. Lipophilic components may be absorbed through the gastrointestinal tract and metabolized in the liver, while other components may undergo different metabolic pathways. The elimination half-life is also variable, reflecting the diverse nature of its constituents.

Pregnancy

Safety in pregnancy has not been established, consult healthcare provider.

Breast-feeding

Consult healthcare provider before use during breastfeeding.

Storage

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

Mechanism of action

The exact mechanism of action of mephenesin is not known. It has been observed to block both inward sodium and inward calcium currents in neurons. It has a physiological effect which opposes that of strychnine.

Pharmacodynamics

Mephenesin reduced neuronal excitability leading to decreases action potentials to muscle fibers which ultimately produces a reduction in spasticity.