ABSTRACT
The drugs described in this chapter — phencyclidine (PCP), ketamine, γ-hydroxybutyrate (GHB), dextromethorphan, and Salvia divinorum — are hallucinogens. The first four appear to operate through the same mechanism: these drugs are all NMDA channel blockers (Jordan et al., 2006), and, at least in vitro, none of them binds to the D2 dopamine receptor. Though their psychological effects appear to be grossly similar, Salvia is a pure κ blocker and it operates via completely different mechanisms than the other group members. The first three drugs are legitimately used as dissociative anesthetics, while dextromethorphan is a cough remedy that shares many of the same properties as the first three agents. Salvia is a pure hallucinogen. It has no known anesthetic effects (nor would any be expected given its known method of action). Patients who are given PCP or ketamine remain conscious but exhibit no apparent response to surgical pain. The same is also true of GHB. None of these anesthetic agents causes muscle relaxation. As a consequence, when any of these drugs is used at surgery (either human or animal) other agents must be administered to produce muscle relaxation. Salvia induces neither anesthesia nor muscle relaxation.
