According to the American Association of Poison Control Centers (AAPCC), there were approximately 20,000 exposures to anticholinergic drugs and plants with 46 major outcomes, but no deaths recorded in 2009 . This demonstrates a significant improvement in outcomes compared to previous data in which there were 51 deaths reported [2-9]. Anticholinergic toxicity is commonly encountered, and familiarity with the management of this syndrome is essential for the emergency clinician.
The basic mechanisms and management of anticholinergic poisoning is reviewed here. Discussions of specific agents that can cause an anticholinergic toxidrome and the general approach to the poisoned patient are found separately. (See "General approach to drug poisoning in adults".)
A summary table to facilitate emergent management of anticholinergic overdose is provided (table 1).
Over 600 compounds have anticholinergic properties, including prescription drugs, over-the-counter medications, and plants (table 2).
Examples of classes of medications with anticholinergic properties include: antihistamines (eg, diphenhydramine), tricyclic antidepressants (eg, amitriptyline), sleep aids (eg, doxylamine), cold preparations, scopolamine, and tainted illicit street drugs (eg, heroin "cut" with scopolamine). Atropine, a belladonna alkaloid, is a commonly used anticholinergic medication for the treatment of bradyarrhythmias.