Ketamine   Ketamine, also called K, Vitamin K, Special K, Jet, among other street names, is a derivative of PCP and is commonly understood to be a "club drug" or "designer drug." It appears as either a white/off-white powder or a liquid, and can be snorted, injected, or orally ingested, though injection (intramuscular) is the most popular means of use.   Ketamine is produced commercially for use as a veterinary anesthetic in the United States and is often acquired for use by theft from veterinary clinics. It is also smuggled from other sources, such as legitimate pharmacies in Mexico.   Ketamine has hallucinogenic properties: in low doses, it produces a dream-like state. At higher doses, it can cause memory loss, learning impairment, loss of motor control, paralysis, high blood pressure, and respiratory distress. Very high doses (~ 1 gram) can be fatal. Long-term use increases the risk of heart attack and stroke. Like many other club drugs, Ketamine is often believed to be harmless by teenagers, causing an increase in experimentation with the drug.