Which of the following is an antiparkinsonian agent with strong anticholinergic properties?

• A. Trihexyphenidyl
• B. Levodopa
• C. Clozapine
• D. Scopolamine

Answer: (A)

Anticholinergic drugs can help balance the brain signals that contribute to Parkinsonian tremor and rigidity. Among the options, the one that is specifically used as an antiparkinsonian agent with strong anticholinergic (muscarinic-blocking) properties is trihexyphenidyl. It directly blocks acetylcholine activity in the brain, which helps reduce symptoms caused by the relative excess of cholinergic activity due to dopamine loss in Parkinson’s disease.

Levodopa works by replenishing dopamine, not by blocking acetylcholine, so it doesn’t have strong anticholinergic properties. Clozapine is an antipsychotic with some anticholinergic effects but is not used as an antiparkinsonian agent. Scopolamine is a muscarinic antagonist used for motion sickness and other indications, not for treating Parkinsonian motor symptoms.