Scientific Essay from the year 2012 in the subject Chemistry - Other, grade: 3, University of Mosul, course: Dental Chemistry, language: English, abstract: The present study was undertaken to extract ketamine powder from ketamine hydrochloride by precipitate ketamine. After that we examine the purity of this powder by infra-red (FTIR) and ultra-violet(UV) spectroscopy. ketamine gel in different concentrations was prepared ( 0.5 , 1 , 5 , 10 , 15 )% to evaluate the antinociceptive activity. ketamine powder was seen is pure and this show in infra-red and ultra-violet scanner. Ketamine gel at concentrations 0.5, 1, 5, 10,15) % produce antinociceptive in mice (5.6±2.2) (4.4±2.0) (8.2±4.3) (10.6±5.2) (8±2.1) second after 2 min respectively by using a hot plate test in comparison with control(2.4±2). The percentage of maximum possible effect (MPE) increased from (9.9) % in control group to (23.3) (18.3) (34.2) (44.2) (33.3)% respectively according to the concentrations of ketamine gel after 2 min . Purification of ketamine powder from ketamine solution and use as a gel to could be of value relief pain by topical application.