Which medication is used to treat xerostomia?

Salagen, or pilocarpine, is specifically indicated for the treatment of xerostomia, a condition characterized by dry mouth resulting from reduced saliva production. Pilocarpine acts as a cholinergic agonist, stimulating the salivary glands to increase saliva production and thus alleviating the symptoms of dry mouth. This is particularly beneficial for patients who may experience xerostomia due to conditions such as Sjögren's syndrome or as a side effect of certain medications or radiation therapy for head and neck cancers.

The other medications listed do not have this therapeutic role. Metoclopramide is primarily used as an antiemetic and for gastrointestinal motility disorders. Lisinopril is an ACE inhibitor indicated for hypertension and heart failure management, and it does not have any effect on saliva production. Similarly, simvastatin is a statin used to manage cholesterol levels and does not address the symptoms of dry mouth. Thus, pilocarpine is the most appropriate choice for treating xerostomia.