A patient with Parkinson's disease is prescribed a medication to help manage tremors. This drug acts by blocking muscarinic receptors in the central nervous system. Which of the following adverse effects is most likely to be experienced by this patient?

✓ Correct Answer: Option D

Antimuscarinic drugs block cholinergic receptors, leading to anticholinergic side effects. These include dry mouth, blurred vision, constipation, tachycardia, and urinary retention. Diarrhea, bradycardia, and increased salivation are typically seen with cholinergic stimulation.