Nurse is reinforcing teaching with a client who takes benztropine to treat Parkinson's Disease. The nurse should instruct client which is an adverse effect of the medication?

• A. Urinary retention
• B. Dry mouth
• C. Drowsiness
• D. Headache

Answer: (D)

Benztropine is an anticholinergic used in Parkinson disease to balance acetylcholine and dopamine by blocking muscarinic receptors in the CNS and periphery. Adverse effects come from this anticholinergic action and can involve both the peripheral system (dry mouth, urinary retention, constipation, blurred vision) and the central nervous system (dizziness, confusion, cognitive changes). Headache is a central nervous system–related adverse effect that can occur with anticholinergic therapy, reflecting CNS involvement even when other typical peripheral effects aren’t as prominent. Therefore, teaching patients to report new or persistent headaches helps detect CNS tolerability issues early. It’s still important to monitor for dry mouth and urinary retention, but headache highlights the CNS side effects that may require hydration checks, review of other medications, or closer observation for potential delirium or cognitive changes.