List three common antimuscarinic side effects and a caution for elderly patients with cognitive impairment.

• A. Increased appetite, weight gain, improved memory; monitor appetite
• B. Dry mouth, constipation, blurred vision; risk of delirium or confusion with cognitive impairment
• C. Diarrhea, sweating, tachycardia; avoid in dehydration
• D. Nausea, rash, hypertension; ignore cognitive status

Answer: (B)

Antimuscarinic drugs block acetylcholine at muscarinic receptors, producing drying and slowing effects in several body systems. Dry mouth results from reduced saliva secretion, constipation from slowed intestinal motility, and blurred vision from impaired accommodation of the eye. In older adults with cognitive impairment, this anticholinergic burden raises the risk of delirium or confusion, so the combination of these three peripheral effects with the warning about cognitive risk is the best-supported choice. The other options either list symptoms not typical for antimuscarinics (such as weight gain or improved memory, diarrhea, or hypertension) or skip the important caution about cognitive status.