Ketamine

Ketamine is a cyclohexanone-derived general anesthetic and NMDA receptor antagonist with analgesic and dissociative properties, producing a trance-like state that provides pain relief, sedation and memory loss during medical procedures; it is also used to treat depression. It works chiefly by blocking NMDA receptor channels, which prevents central sensitization of neurons in the spinal cord's dorsal horn and interrupts pain signaling. Chemist Calvin Stevens synthesized ketamine in 1962 while a professor at Wayne State University and a consultant to the pharmaceutical company Parke-Davis, under the code name CI-581; human testing in 1964 showed advantages over the related compound phencyclidine, and the Food and Drug Administration approved it in 1970, after which it saw extensive military use during the Vietnam War. In 2000, researchers found that ketamine also produces rapid antidepressant effects, a discovery later described as among the most important advances in depression treatment in decades.