Woods' Great Peppermint Cure Cough Syrup

Indications

• Pruritus
• Eczema
• Acne
• Rosacea

Dosage

Children: For children aged 12-17 years, apply up to 3 grams 3-4 times a day, ensuring coverage is less than 10% of body surface area.

Adults: Apply thinly to the affected area 1-2 times a day. Maximum application should cover less than 10% of body surface area, with a total daily maximum of 12 grams.

Mechanism of action

Levomenthol primarily activates the cold-sensitive TRPM8 receptors in the skin. This stimulation leads to a feeling of coolness by inhibiting calcium ion currents in neuronal membranes. Additionally, menthol may exhibit analgesic properties through kappa-opioid receptor agonism, further contributing to its pain-relieving effects.

Pharmacodynamics

Levomenthol is a covalent organic compound that can be synthesized or extracted from peppermint and other mint oils. It induces a cooling sensation when applied topically, inhaled, or ingested, by stimulating cold-sensitive receptors located in the skin. Notably, this effect occurs without a decrease in actual skin temperature, making it useful in topical formulations for managing discomfort.

Pharmacokinetics

Levomenthol is absorbed through the skin upon topical application. Its effects are localized, and it does not significantly enter systemic circulation when used as directed. The onset of action is typically rapid, providing immediate symptomatic relief from conditions like itching and irritation.

Contra-indications

• Severe heart disease
• Severe hepatic impairment
• Glaucoma
• Urinary retention
• History of mania or arrhythmias

Adverse effects

• Drowsiness
• Dizziness
• Headache
• Nausea
• Vomiting
• Dry mouth
• Dry eyes
• Diarrhea
• Constipation
• Skin reactions
• Altered taste
• Blurred vision
• Suicidal behaviors

Interactions

• Tricyclic antidepressants
• Other central nervous system depressants

Precautions

• Avoid application to large areas of the skin
• Use caution in patients with a history of psychiatric disorders
• Caution advised for driving and skilled tasks due to potential somnolence or dizziness

Pregnancy

Manufacturer advises use only if potential benefit outweighs risk.

Breast-feeding

Manufacturer advises use only if potential benefit outweighs risk.

Storage

Store in a cool, dry place, protected from light.

Formulations

• AquaSoothe 1% cream (Menthol 10 mg per 1 gram)
• AquaSoothe 2% cream (Menthol 20 mg per 1 gram)
• Arjun 0.5% cream (Menthol 5 mg per 1 gram)
• Arjun 1% cream (Menthol 10 mg per 1 gram)
• Dermacool 0.5% cream (Menthol 5 mg per 1 gram)
• Dermacool 1% cream (Menthol 10 mg per 1 gram)
• Menthoderm 0.5% cream (Menthol 5 mg per 1 gram)
• Menthoderm 1% cream (Menthol 10 mg per 1 gram)
• Menthoderm 2% cream (Menthol 20 mg per 1 gram)
• Menthoderm 5% cream (Menthol 50 mg per 1 gram)

Indications

• Irritable bowel syndrome
• Dyspepsia
• Nausea
• Headaches
• Respiratory congestion

Dosage

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

Adults: Refer to the relevant product-specific information for dosing recommendations, as peppermint formulations can vary widely.

Mechanism of action

The primary active component, menthol, works by activating the TRPM8 (transient receptor potential cation channel subfamily M member 8) ion channel, which is involved in the sensation of cold and cooling. This action can lead to a localized anesthetic effect, reducing pain and discomfort. Additionally, menthol can cause relaxation of smooth muscle in the gastrointestinal tract, aiding in the relief of digestive symptoms.

Pharmacodynamics

Peppermint exhibits antispasmodic effects, particularly in the gastrointestinal tract, by relaxing the smooth muscles. It also has a mild analgesic effect due to its cooling sensation, which can provide symptomatic relief in various conditions. Furthermore, peppermint oil may have antimicrobial properties, contributing to its use in treating certain infections.

Pharmacokinetics

Menthol is rapidly absorbed after oral administration and is metabolized in the liver. The peak plasma concentration typically occurs within a few hours. The elimination half-life of menthol is approximately 1.5 to 2 hours, and it is primarily excreted in the urine as metabolites. The pharmacokinetics of peppermint oil can vary based on the formulation and route of administration.

Interactions

• peppermint oil + lomitapide: Unknown (increases exposure)

Pregnancy

Peppermint is generally considered safe for use in pregnancy when used in culinary amounts. However, high doses should be avoided due to potential uterine stimulation.

Breast-feeding

Peppermint is considered safe during breastfeeding when used in culinary amounts. Caution is advised with high doses as effects on the infant are not well studied.

Storage

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

Formulations

• Peppermint oil
• Peppermint extract
• Peppermint tea

Mechanism of action

Menthol primarily activates the cold-sensitive TRPM8 receptors in the skin. Menthol, after topical application, causes a feeling of coolness due to stimulation of 'cold' receptors by inhibiting Ca++ currents of neuronal membranes. It may also yield analgesic properties via kappa-opioid receptor agonism.

Pharmacodynamics

Menthol is a covalent organic compound made synthetically or obtained from peppermint or other mint oils. Menthol induces a cooling sensation on the skin upon inhalation, oral ingestion, or topical application by stimulating the cold-sensitive receptors expressed on the skin, without actually causing a drop in the skin temperature.