**Question:** Anticholinergic drug used in parkinsonism -

A. Benztropine
B. Ropinirole
C. Levodopa
D. Amantadine

**Correct Answer:** A. Benztropine

**Core Concept:**
Anticholinergic drugs are medications that work by blocking the action of acetylcholine, a neurotransmitter involved in various physiological processes, including muscle contraction, bladder function, and cognitive functions. In Parkinson's disease, the main symptom is a decrease in dopamine levels in the brain, particularly in the substantia nigra region, leading to motor and non-motor symptoms. Anticholinergic drugs are used to alleviate the non-motor symptoms, such as urinary incontinence, dry mouth, and excessive sweating, which are commonly associated with Parkinson's disease.

**Why the Correct Answer is Right:**
Benztropine (Cogentin) is an anticholinergic drug primarily used to manage the non-motor symptoms of Parkinson's disease. It works by blocking the effects of acetylcholine, reducing its excessive stimulation of muscarinic receptors in the central nervous system and periphery. By doing so, Benztropine helps alleviate symptoms like urinary incontinence, dry mouth, and excessive sweating.

**Why Each Wrong Option is Incorrect:**

A. Ropinirole (Requip): Ropinirole is a dopamine agonist, not an anticholinergic drug. It is primarily used to treat Parkinson's disease by enhancing dopamine release in the brain.

B. Levodopa (Sinemet): Levodopa is another dopamine precursor used in the treatment of Parkinson's disease, although it is primarily used to increase dopamine levels in the brain. It does not primarily target non-motor symptoms like Benztropine does.

C. Amantadine (Symmetrel): Amantadine is primarily an antiviral agent used in the treatment of viral infections. In Parkinson's disease, it is primarily used as a dopamine agonist, not an anticholinergic drug.

**Clinical Pearl:**

In Parkinson's disease, while dopaminergic agents like Ropinirole and Levodopa are essential for managing motor symptoms, anticholinergic drugs like Benztropine are utilized to address the non-motor symptoms associated with the disease. A comprehensive treatment plan for Parkinson's disease involves a combination of both dopaminergic and anticholinergic drugs to address both motor and non-motor symptoms effectively.