Deliriants

Competitive antagonism at muscarinic acetylcholine receptors, centrally and peripherally. The result is delirium, and its distinction from psychedelia is not one of degree: the hallucinations are indistinguishable from the room, insight is gone rather than strained, and memory of the episode is fragmentary or absent. That is why this is its own subject and not a subclass of Psychedelics, where a person knows what is happening to them.

Two families sit here — the tropane alkaloids of Datura and belladonna, and the first-generation antihistamines at doses far above their labelled use. The harms are the peripheral half of the same blockade: tachycardia, hyperthermia through lost sweating, urinary retention, blurred vision. All of it is additive with anything else antimuscarinic, including tricyclics, some antipsychotics and travel-sickness remedies, and injury sustained during the delirium is a large part of what actually happens to people.