Ketamine is similar to the related drug phencyclidine (PCP) and is called a dissociative anesthetic due to its ability to induce a lack of responsive awareness not only to pain but also to the general environment. The subjective experiences of ketamine intoxication range from pleasant dreams to intensely visual or polysensual hallucinations. Occasionally a brief, full-blown delirium occurs. Despite warnings about its potential for abuse, ketamine eventually appeared on the streets in the early 1970's in the same way that PCP did in the 1960's. By the early 1980's various preparations of ketamine were available on the street with names such as Special K, 1980 acid, and Super C. In the 1990's the social and recreational use of ketamine reemerged in the context of a subcultural music phenomenon known as acid house music. Large parties that are usually called raves combine acid house music and ketamine use. Ketamine abuse appears to be increasing. Clinically significant consequences range from occasional flashbacks to delirious reactions, as well as every type of dissociative symptoms. 26 references (Author abstract modified)