Pharmacologic actions of CI‐581, a chemical derivative of phencyclidine, were determined in 20 volunteers from a prison population. The results indicate that this drug is an effective analgesic and anesthetic agent in doses of 1.0 to 2.0 mg. per kilogram. With intravenous administration the onset of action is within 1 minute and the effects last for about 5 to 10 minutes, depending on dosage...