HUMAN SALIVA- A NATURAL PAIN KILLERSurprisingly, human saliva has been reported to contain a natural painkiller. All over the world, the compound Morphine is the popular painkiller for clinical as well as non-clinical purposes. But prolonged use of such synthetic painkillers causes addiction and tolerance. Hence natural ones are preferred which might help to avoid these side effects. So far, reports of natural painkillers available are very rare. Recently, human saliva has been found to contain a painkiller with six times more potency than morphine as exhibited in rat trials. The compound opiorphin prolongs body's own defense mechanism against pain as reported by, Catherine Rougeot and her colleagues of the Pasteur Institute in Paris, France, in Proceedings of the National Academy of Sciences .This action is achieved by preventing the breakdown of enkephalins thereby activating opiate receptor which in turn block pain signals from reaching the brain. This is the first natural pain killing substance mentioned to be produced by human body. Actually opiorphin does not possess any painkilling role ordinarily, but it plays a general role in protecting other chemicals in the body from being broken down. In rats, opiorphin reduced the pain induced by both physical and chemical means. However, this new substance must be tested further to confirm its effectiveness for being used as a drug. Moreover, the unforeseen side effects, if any, also must be verified thoroughly before its launching for commercial purposes.