Ketamine is a dissociative anesthetic that has some hallucinogenic effects and is used as an injectable, short-acting anesthetic for use in humans and animals. It is referred to as a “dissociative anesthetic” because it makes patients feel detached from their pain and environment. Ketamine is classified as a Schedule III substance under the Controlled Substances Act in the United States. Schedule III drugs, which include codeine and anabolic steroids, have less potential for abuse than Schedule I and II drugs. Ketamine is not classified as an opioid (narcotic) or barbiturate.