A recently discovered receptor -- known as TRPM8 -- is found in a small percentage of nerve cells in human skin, and the study revealed that TRPM8 is activated by cool temperatures such as those created by small doses of the cooling compound. When activated, TRPM8 prevents pain messages from traveling to the brain.
The study, published in the journal Current Biology, also noted that the compounds could provide pain relief for chronic pain sufferers -- such as arthritis sufferers or people who endure pain from nerve damage or spinal injury -- for whom regular painkillers are often ineffective. The compound would likely grant this benefit with few side effects, the study said, because it is applied externally.
"Conventional painkillers such as morphine are often ineffective in cases of chronic pain and simply lowering the temperature of the skin is too inexact," said professor Susan Fleetwood-Walker, one of the lead researchers. "Our discovery means that patients can be given low doses of a powerful pain killer, delivered through the skin, without side effects.
"We hope clinical trials on the compounds will begin within the year," she said.
"We don't need some synthetic version of this medicine," said Mike Adams, a proponent natural health. "Nature has already invented this medicine, and common plants synthesize these compounds automatically, without demanding royalty payments or pharmacy fees. Simply use the healing plants that already exist!"