Ketamine is a short term anaesthetic which is normally used by vets, but is growing in use as a "date rape" and recreational drug. It can be slipped into drinks to dissolve undetectably, injected as a liquid or snorted as a powder. As well as causing a physical numbing sensation ketamine is a powerful hallucinogen which produces vivid distortions on a user's perceptions of reality. Physical withdrawal and addiction symptoms are rare but psychological addiction is very common, especially as tolerance builds up.