From the "Report on the risk assessment of ketamine in the framework of the joint action on new synthetic drugs", published in 2002 by the European Monitoring Centre for Drugs
and Drug Addiction.

A total of 12 deaths in which ketamine was identified were noted between 1987 and 2000, including seven from the United States. Only three reported fatal cases involving ketamine alone were identified. Two reports concern mixed drugs fatalities. In one case, ketamine had only a minor role. For the remaining six cases, insufficient details were available to be evaluated properly.
In the three cases involving only ketamine, the routes of administration were intramuscular or intravenous and the cause of death was mainly overdose (multiple intramuscular doses or accidental intravenous overdose), in line with preclinical findings. In the other cases involving ketamine mixed with other drugs, the observed lower ketamine concentrations indicate that drug interaction may have contributed to these deaths. Substances with CNS/respiratory depressant effects, like ethanol, opioids, barbiturates and benzodiazepines, or drugs with cardiostimulant effects, like cocaine or amphetamines, may increase ketamine acute toxicity.

Held at Melbourne University's Copland Theatre in Australia, this event featured presentations from Michael Bock, Vince Cakic, David Caldicott, Deva Daricha, Richard King, Anna Kokavec, Tim Payne, Julian Raxworthy, Des Tramacchi, Torsten Wiedemann. Topics covered included psychoactive mushrooms, shamanism, Ephedra, wine, Tabernanthe iboga, absinthe, toot, books on psychoactives, the ketamine model of schizophrenia, and harm reduction.

"The American Society of Anesthesiologists firmly opposes the use of ketamine or any other sedative/hypnotic agent to chemically incapacitate someone for a law enforcement purpose and not for a legitimate medical reason. Ketamine is a potent analgesic, sedative and general anesthetic agent which can elevate blood pressure and heart rate, and can lead to confusion, agitation, delirium, and hallucinations. These effects can end in death when administered in a non-health care setting without appropriately trained medical personnel and necessary equipment."