Neuroscientists at the University of Edinburgh in Scotland have identified the molecular mechanism of action of BenGay, topical mint oil, and other cooling remedies:
The Greek scholar Hippocrates treated sprains, joint pains and inflammation by cooling the skin, and traditional Chinese remedies used mint oil to the same end.
Now University researchers have discovered that cooling chemicals which have the same properties as mint oil have a dramatic pain-killing effect when applied in small doses to the skin.
Unlike conventional pain killers, these compounds are likely to have minimal toxic side effects, especially because they are applied externally to the skin. This should mean they are ideal for chronic pain patients for whom conventional pain killers often do not work.
The study explains that the ‘mint oil’ and related chemical compounds act through a recently discovered receptor (a protein which is capable of binding with these chemicals) which is found in a small percentage of nerve cells in the human skin.
When this receptor, called TRPM8, is activated by the cooling chemicals or cool temperatures, it inhibits the ‘pain messages’ being sent from the locality of the pain to the brain.
Thus, the new treatment makes good use of the body’s own mechanisms for killing pain.