Deliriant

Deliriants are a subclass of hallucinogen. The term was coined in the early 1980s to distinguish these drugs from psychedelics such as LSD and dissociatives such as ketamine, due to their primary effect of causing delirium, as opposed to the more lucid and less disturbed states produced by other types of hallucinogens, where rational thought is better preserved. The term generally refers to anticholinergic drugs, which are substances that inhibit the function of the neurotransmitter acetylcholine.