Ketamine is a Schedule III controlled substance because it has some medically accepted uses but also has some potential for abuse and dependence, particularly psychological dependence. You may receive ketamine from a doctor if he or she needs to anesthetize you for only a short period of time. 

According to the Drug Enforcement Agency, ketamine can cause amnesia, i.e., make you lose your memory of the time that you are on it. It can relieve pain and induce a state of sedation. It can also cause your body to become completely immobile. These qualities make ketamine an effective anesthetic. Unfortunately, they also make it an attractive substance for abuse. 

Abuse of ketamine 

Authorities refer to ketamine as a club drug because its use is common at raves and dance clubs by young adults looking to enhance their experience. In addition to the effects already noted, ketamine also has hallucinogenic properties, i.e., it alters your perceptions. The effect is short-lived, lasting only about 30 to 60 minutes. For many, this is preferable to a trip induced by taking LSD, which can last for hours. 

Though many of the effects are short-term, some people have reported experiencing flashbacks several weeks after taking it. Because ketamine causes those who take it to relax and detach from their environment, it can also be a date rape drug. 

Administration of ketamine 

Ketamine can exist in either liquid or powdered states. The liquid is injectable, or it is possible to mix it with a drink and consume it that way. When heated, liquid ketamine evaporates, leaving crystals behind. It is then customary to grind the crystals into powder and either smoke it or snort it. 

Ultimately, ketamine is legal if used according to applicable laws for legitimate medical purposes. Otherwise, the abuse of ketamine is illegal.