What cholinergic agent is commonly used to treat motion sickness?

Scopolamine is commonly used to treat motion sickness due to its anticholinergic properties, which help alleviate nausea and vomiting associated with motion sickness. By blocking the action of acetylcholine in the vestibular system, scopolamine reduces the excitability of the neuro pathways that lead to nausea. It is typically administered as a transdermal patch, making it a convenient option for travelers.

In contrast, atropine, while being an anticholinergic agent as well, is primarily used for other indications such as bradycardia and as a pre-anesthetic to reduce secretions rather than for motion sickness. Donepezil is a cholinesterase inhibitor used primarily in the treatment of Alzheimer’s disease and cognitive decline; it does not have a specific role in treating motion sickness. Pilocarpine, a cholinergic agonist, is used mainly to treat conditions such as glaucoma or xerostomia (dry mouth), and it has no indication for motion sickness. Thus, scopolamine stands out as the most relevant choice for treating this condition.