levomenthol

Action and Spectrum

Actions and Spectrum: 

levomenthol, commonly known as menthol, is a naturally occurring compound found in mint oils, particularly peppermint and spearmint. It is widely used for its cooling and soothing properties, making it a popular ingredient in various pharmaceutical, cosmetic, and personal care products.  

• Cooling Sensation: levomenthol produces a cooling sensation by activating the transient receptor potential melastatin 8 (TRPM8) ion channels on sensory nerves. TRPM8 is a cold-sensitive receptor, and when menthol binds to it, it triggers a response that is interpreted by the brain as a cooling or refreshing sensation. 
• Analgesic (Pain Relief) Effect: The cooling sensation produced by menthol can also have an analgesic effect, helping to alleviate minor aches and pains. It may act by inhibiting pain signals and reducing the perception of pain. 
• Anti-Itch Properties: levomenthol is often used topically to relieve itching associated with conditions such as insect bites, rashes, or minor skin irritations. It can provide a soothing effect and help reduce the urge to scratch. 
• Respiratory Benefits: menthol is commonly used in cough drops, throat lozenges, and inhalation products due to its ability to produce a cooling sensation and provide relief to the throat and respiratory passages. It can help reduce the perception of irritation and ease breathing. 

levomenthol’s spectrum of activity is primarily related to its sensory effects, such as cooling, soothing, and refreshing sensations. It is commonly used in topical formulations, including creams, ointments, balms, and lotions, for its local effects on the skin and mucous membranes. While it is not a broad-spectrum antimicrobial or anti-inflammatory agent, its properties make it suitable for relieving specific symptoms associated with pain, itching, and irritation.

Drug Interaction

Adverse Reaction

Frequency not defined 

Sickness 

Drowsiness 

Severe tummy pain 

Dizziness 

Impaired coordination 

Black Box Warning

None 

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

• Allergic Reactions: Individuals with known allergies to menthol or mint oils should avoid products containing levomenthol. Allergic reactions may include skin rashes, itching, swelling, or difficulty breathing. 
• Children Under 2 Years Old: Products containing menthol are often not recommended for use in infants and children under the age of 2 due to the risk of adverse reactions and potential respiratory distress. 
• Respiratory Conditions: Individuals with respiratory conditions such as asthma or chronic obstructive pulmonary disease (COPD) may be sensitive to menthol’s cooling effect and should use products containing menthol with caution. Inhaling menthol vapors could trigger respiratory symptoms in susceptible individuals. 
• Hypersensitivity to Cooling Sensation: Some people may be hypersensitive to the cooling sensation produced by menthol, which could lead to discomfort or irritation. 
• Skin Conditions: People with sensitive skin or certain skin conditions may experience irritation when using products containing menthol. It’s advisable to perform a patch test before widespread application. 
• Open Wounds or Broken Skin: The application of menthol-containing products on open wounds or broken skin may irritate and should be avoided. 

Caution: 

• Skin Sensitivity: Some individuals may be more sensitive to menthol, and it could cause skin irritation, redness, or a burning sensation. It’s advisable to perform a patch test on a small area before applying products containing menthol more widely. 
• Eye Contact: Avoid contact with the eyes, as menthol can irritate. If accidental contact occurs, rinse the eyes thoroughly with water. 
• Avoid Ingestion: Ingesting pure menthol or consuming large amounts of menthol-containing products can be toxic. Keep menthol products out of reach of children and avoid swallowing or ingesting them.

Pregnancy / Lactation

Pregnancy consideration: Insufficient data available 

Lactation: Excretion of the drug in human breast milk is unknown 

Pregnancy category: 

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence, these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

The pharmacology of levomenthol, commonly known as menthol, involves its interaction with various receptors and ion channels, leading to specific physiological responses. 

TRPM8 Activation: 

• The primary mechanism of action for menthol is its interaction with the transient receptor potential melastatin 8 (TRPM8) ion channel. 
• TRPM8 is a cold- and menthol-sensitive receptor found on sensory nerve endings, particularly in the skin and mucous membranes. 
• Activation of TRPM8 by menthol leads to a cooling or refreshing sensation, as it triggers a response that the brain interprets as a drop in temperature. 

Cooling Sensation: 

• menthol produces a cooling effect by activating TRPM8 channels, which are involved in the perception of temperature. 
• This cooling sensation is exploited in various products, such as topical analgesics, balms, and skin care items, to provide relief from minor aches, pains, and skin irritations. 

Analgesic Effect: 

• The activation of TRPM8 channels by menthol has analgesic properties, contributing to its use in products designed to relieve pain and discomfort. 
• Menthol’s analgesic effect may involve the modulation of pain signals, leading to a reduction in the perception of pain. 

Anti-Itch Properties: 

• menthol is known for its anti-itch properties, and it is often included in formulations to relieve itching associated with insect bites, rashes, or minor skin irritations. 
• The cooling effect of menthol can help alleviate the urge to scratch and provide a soothing sensation. 

Pharmacokinetics: 

Absorption 

When inhaled, menthol vapors can be absorbed through the respiratory tract. 

Distribution 

After absorption, levomenthol is distributed throughout the body via the bloodstream. It tends to accumulate in tissues with high blood flow, and its distribution may be influenced by factors such as blood perfusion and tissue composition. 

Metabolism 

levomenthol is primarily metabolized in the liver. The metabolism may involve processes such as oxidation, glucuronidation, and sulfation. The primary metabolites are excreted via urine. 

Elimination and Excretion 

The metabolites of levomenthol are excreted mainly through the urine. The kidneys play a significant role in eliminating these metabolites from the body. The elimination half-life of levomenthol can vary based on factors such as individual differences, formulation, and route of administration.

Adminstartion

Administration: 

Oral administration 

menthol is commonly found in tablets and throat drops designed to soothe the throat. These products are dissolved in the mouth, allowing menthol to be released and provide relief. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: levomenthol 

Why do we use levomenthol? 

levomenthol, commonly known as menthol, is a versatile compound that finds application in various products due to its distinctive cooling and soothing properties.  

• Topical Analgesics: menthol is a crucial ingredient in many topical analgesic products, such as creams, balms, and patches, designed to provide relief from minor aches and pains. It produces a cooling sensation and may help reduce the perception of pain. 
• Respiratory Products: Inhaling menthol vapors can help soothe the respiratory tract. Menthol is often used in products like throat lozenges, cough drops, and inhalation solutions to provide relief from throat irritation and coughing. 
• Oral Care Products: menthol is included in toothpaste and mouthwash formulations for its refreshing flavor and cooling sensation. It may contribute to a clean and fresh feeling in the mouth. 
• Skin Care Products: Due to its soothing properties, menthol is used in skincare products such as lotions, creams, and balms. It can provide a refreshing sensation and may be included in products designed to relieve itching or minor skin irritations. 
• Hair Care Products: menthol is sometimes added to shampoos and conditioners for its cooling effect on the scalp. It can contribute to a refreshing and invigorating experience during hair care routines.