The aim of the present study was extract pure ketamine powder from ketamine hydrochloride solution; ketamine gel in different concentrations was prepared to detect the therapeutic effectiveness of it as analgesic in the form of a topical application in both human and laboratory animals.The results demonstrated that the purified ketamine was pure according to IR, UV, CHN analysis and melting point. Ketamine gel also is safe to be used topically and not irritant according to the skin irritation test, because the mean value of skin irritation index (SII) for erythema and edema was found to be zero after applied of ketamine gel in different concentrations.A significant analgesic effect of ketamine gel in humans was induced by the test formulation containing 0.5% ketamine gel and the percentages of non, mild, moderate and severe pain were (46.4, 32.1, 17.9 and 3.6)%,respectively. It was concluded from this study that a pure ketamine powder can be prepared and could be of value when used as...
