Hallucinogens

This chapter highlights the similarities in chemical structure and physiologic effects of hallucinogens, as well as their metabolism, therapeutic uses and potential for misuse or abuse. Special attention is given to the testing process, with an emphasis on interpretation of test results. Hallucinogens are drugs that alter an individual's perception of reality. The classic hallucinogens include lysergic acid diethylamide (LSD), psilocybin, and mescaline. LSD is a derivative of lysergic acid, an alkaloid that occurs naturally in the fungus Clavicepspurpurea . LSD, psilocybin, and mescaline exert their perception-altering effects by acting on neural circuits in the brain that use serotonin as the neurotransmitter. Phencyclidine (PCP) and ketamine produce their effects by interfering with the activity of the neurotransmitter glutamate. PCP is hydroxylated to form inactive metabolites, which are then conjugated to glucuronic acid and excreted in urine. The chapter provides dissociative drugs phencyclidine and ketamine.