A specific urinary color test for triflupromazine (Vesprin) is reported in which 1 ml. of urine is mixed with 1 ml. 10% trichloracetic acid. To this mixture 1 ml. of 1/1000 molar solution of uranyl nitrate in concentrated hydrochloric acid is added. The resulting color is read within 30 seconds against a color chart showing three color intensities, marked +, ++ and +++, for daily drug doses ranging from 10 to 600 mg. of drug. No false negatives were encountered, and 0.6% false positive tests were seen. Potential factors of interference are discussed.Abstract Teaser