Pharmacology · single question
Which medication INCREASES salivation (i.e., does NOT cause dry mouth)?
Show answer and explanation
Correct answer: B. Pilocarpine (muscarinic agonist)
Pilocarpine is a muscarinic (M3) cholinergic agonist that STIMULATES salivary and sweat gland secretion. It is used clinically to treat xerostomia in Sjögren's syndrome and post-radiation patients. All other options DECREASE saliva: scopolamine (anticholinergic), amitriptyline (TCA with anticholinergic effects), HCTZ (diuretic-induced xerostomia).
- A. ❌ Scopolamine blocks muscarinic receptors → anticholinergic effect → dry mouth.
- B. ✅ Pilocarpine stimulates muscarinic receptors → INCREASES salivation; used to treat xerostomia.
- C. ❌ Amitriptyline has significant anticholinergic side effects → xerostomia.
- D. ❌ HCTZ (thiazide diuretic) causes xerostomia.