Used to treat occasional minor irritation, pain, sore mouth, and sore throat as well as cough associated with a cold or inhaled irritants.
Menthol is a covalent organic compound made synthetically or obtained from peppermint or other mint oils. Menthol's ability to chemically trigger cold-sensitive receptors in the skin is responsible for the well known cooling sensation that it provokes when inhalated, eaten, or applied to the skin. It should be noted that menthol does not cause an actual drop in temperature.
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.
Menthol, DL: ORAL (LD50): Acute: 2900 mg/kg [Rat], 3100 mg/kg [Mouse]. DERMAL (LD50): Acute: 5001 mg/kg [Rabbit].