Thymol is a monoterpene phenol derivative of cymene, C10H14OH, isomeric with carvacrol, found in oil of thyme, and extracted as a white crystalline substance of a pleasant aromatic odor and strong antiseptic properties. It is also called "hydroxy cymene".
The crystalline substance thymol was discovered by Caspar Neumann in 1719 and synthesized in pure form in the year 1842 by von M. Lallemand characterized through elementary chemical analysis. Using this, he was able to discover the correct ratio of carbon, hydrogen, and oxygen that make up thymol molecules. Friedrich Ferdinand Runge also studied the chemistry of this substance. Alain Thozet und M. Perrin first published the crystral structure analysis with the exact determination of the structural atoms.
The Bee Balms (Monarda fistulosa and Monarda didyma) are natural sources of thymol, a primary active ingredient in modern commercial mouthwash formulas. The Blackfeet Indians recognized this plant's strong antiseptic action, and used poultices of the plant for skin infections and minor wounds. A tea made from the plant was also used to treat mouth and throat infections caused by dental caries and gingivitis.
In a 1994 report released by five top cigarette companies, thymol was listed as one of 599 additives to cigarettes. It is said to be added to improve the flavor of cigarettes, but as mentioned above, it relaxes the trachea.
There is also evidence supporting the belief that thymol when applied two to three times daily, can eliminate certain kinds of fungal infections that affect finger nails and toe nails in humans. Regular application to the affected nail over periods approximating three months, has been shown to eliminate the affliction by effectively preventing further progress; by simply cutting the nail as one normally would, all infected material is eventually eliminated.
Thymol has GABAnergic activity, a mechanism of action similar to other depressants such as secobarbital, methaqualone and diazepam. It bears close similarity to the widely used anaesthetic propofol (2,6-diisopropylphenol). Because it is less potent, thymol could potentially be abused like the more common depressants. Propofol is extremely dangerous because of its very steep dose-response curve and high potency. It is commonly abused among anesthesiologists and nurses, many times causing death. Because of thymol's lowered potency and safer dose-response curve, it could feasibly be abused as a legal depressant. Because propofol is not scheduled, thymol is neither a controlled substance nor a controlled substance analogue in the US and the UK. Because of its widespread availability in food products, it is unlikely to ever come under control.