Which two antimuscarinic agents are primarily used to treat Parkinson's disease?

The two antimuscarinic agents primarily used to treat Parkinson's disease are Benztropine and Trihexyphenidyl. These medications are effective in managing the tremors and rigidity associated with Parkinson's due to their ability to restore the balance between acetylcholine and dopamine in the central nervous system.

In Parkinson's disease, the depletion of dopamine leads to an excess of acetylcholine activity, which contributes to the motor symptoms. By blocking muscarinic receptors, Benztropine and Trihexyphenidyl reduce the effects of acetylcholine, helping to alleviate these symptoms and providing symptomatic relief for patients. Their role in Parkinson's treatment differentiates them from the other medications listed, which are primarily used for conditions unrelated to Parkinson's disease.

The other agents from the provided choices serve different purposes: Darifenacin and Oxybutynin are used primarily for overactive bladder, while Aclidinium and Ipratropium are bronchodilators used in respiratory conditions like asthma and COPD. Solifenacin and Tolterodine, like Darifenacin and Oxybutynin, are also indicated for urinary conditions. This distinction underscores the specific role that Benztropine and Trihexyphenidyl