An 18-week double-blind crossover study of 61 "hard core" geriatric patients with organic brain syndrome compared the efficacy of pentylenetetrazol (Metrazol) with placebo, using a dosage level of 600 mg. per day. Five rating instruments were administered at the beginning, the crossover point, and the end of the study. The results demonstrated no superiority of Metrazol over placebo. Women improved more than men under both conditions. The sequence of administration of medications was not significant. Side effects were noted in only 15 percent of patients on Metrazol and eight percent on placebo.Abstract Teaser