Scopolamine

At low medical doses scopolamine mainly causes dry mouth, blurred vision, and drowsiness. At the higher doses used recreationally or criminally it produces a full anticholinergic delirium; realistic hallucinations mistaken for reality, profound confusion and memory loss, and the classic toxidrome (blurred vision, flushing, dangerous overheating, dry mouth), plus racing heart, urinary retention, seizures, and death. It leaves people suggestible and amnesic, which is exactly why it is dangerous in the wrong hands. Never stack it with other anticholinergics or antihistamines, and elderly people are especially vulnerable. Not medical advice.

Scopolamine is a muscarinic antagonist that crosses into the brain freely, so its dominant interaction is additive anticholinergic burden. Alongside tricyclics, first-generation antihistamines, low-potency antipsychotics, antiparkinson agents or bladder antimuscarinics it produces confusion, disorientation, frank delirium, dry mouth, blurred vision, urinary retention and impaired heat dissipation. Older patients reach that threshold on far less, and the combination is a recognized cause of hospital delirium.

Alcohol, benzodiazepines, opioids and other CNS depressants add to its sedation and to the amnestic effect it produces at higher exposure.

Pharmacologically it opposes cholinesterase inhibitors such as donepezil, rivastigmine and pyridostigmine, and it antagonizes prokinetics such as metoclopramide.

By slowing gastric emptying and gut transit, scopolamine can delay or blunt absorption of oral drugs taken with it, which is easy to overlook because the effect is silent.

Checking a whole stack? Run it through interactions + stacks.