Anticholinergic side effects

Anticholinergic side effects

Some anti-Parkinson, antivertigo, and incontinence agents depend on anticholinergic activity as the mechanism of drug action. However, as people age, the therapeutic range for these agents becomes smaller, exposing elderly patients to a greater risk of toxicity. Also remember that many drugs with other primary mechanisms of action have significant anticholinergics effects. Thus, if an older patient is taking one or more of these agents, toxicity can also occur.

Drugs that can cause anticholinergic side effects are shown below:

Antidepressants: amitriptyline, imipramine, paroxetine

Antihistamines: diphenhydramine, chlorpheniramine

Antivertigo: betahistine,

scopalamine, meclizine

Antiemetics: prochlorperazine, promethazine, hydroxyzine

Antispasmotics: clidinium, dicyclomine, hyoscyamine

Muscle relaxants: cyclobenzprine, orphenadrine

Urinary antispasmotics: oxybutynin

Mydriatics: atropine, homotropine, tropicamine

Antiparkinson agents: benztropine, trihexyphenidyl

Antidiarrheals: diphenoxylate-atropine

Antipsychotics: chlorpromazine, thioridazine, clozapine


Which of the following scenarios can lead to anticholinergic delirium? An elderly patient with:


Besides delirium, arrhythmias and seizures, other anticholinergic effects include: