What It Is:

Ketamine hydrochloride is a quick-acting anesthetic that is legally used in both humans (as a sedative for minor surgery) and animals (as a tranquilizer). At high doses, it causes intoxication and hallucinations similar to LSD.

Sometimes Called:

K, Special K, vitamin K, bump, cat Valium, Kit Kat, Super acid, Purple

How It's Used:

In different forms, ketamine can be snorted, swallowed, smoked, or injected. Users often use it along with other drugs such as Ecstasy (called kitty flipping) or cocaine or sprinkle it on marijuana blunts.

What It Does:

People who use ketamine can become psychologically dependent on it to feel good, deal with life, or handle stress.

Users may become delirious, hallucinate, and lose their sense of time and reality. The trip — or K-hole — that results from ketamine use lasts up to 2 hours. Users may become nauseated or vomit, and have problems with thinking or memory.

At higher doses, ketamine causes movement problems, body numbness, and slowed breathing. Overdosing on ketamine can stop breathing and cause death.