Arylcyclohexylamines (also written arylcyclohexylamine) are a chemical class of dissociative anesthetic compounds characterized by the presence of a phenyl (or substituted aryl) group and an amine attached to a cyclohexane ring. The class includes some of the most pharmacologically significant dissociative substances known, most notably phencyclidine (PCP) and ketamine, as well as a growing array of novel research chemicals including methoxetamine (MXE), deschloroketamine (DCK), 2-FDCK, and numerous PCP analogs.
Arylcyclohexylamines produce their characteristic dissociative effects primarily through antagonism of N-methyl-D-aspartate (NMDA) glutamate receptors in the central nervous system. NMDA receptor blockade disrupts normal glutamatergic signaling in corticolimbic circuits, producing a dose-dependent spectrum of effects ranging from mild perceptual distortions and analgesia at low doses, through pronounced dissociation, depersonalization, and ego dissolution at intermediate doses, to the complete sensory isolation and internally generated dreamscape known in ketamine culture as the "K-hole" at high doses.
The class is pharmacologically diverse — members vary considerably in potency, duration, receptor selectivity, and additional mechanisms including sigma receptor agonism, dopamine reuptake inhibition, and opioid receptor interactions. Ketamine has achieved exceptional clinical prominence as an anesthetic and, increasingly, as a rapid-acting antidepressant. PCP, once explored clinically, is now known primarily as a substance of abuse with a more severe adverse effect profile than ketamine. The newer research chemicals represent an ongoing expansion of the chemical space, with varied and often incompletely characterized pharmacological profiles.