Pilocarpine is used in acute angle-closure glaucoma primarily because it:
- A Contracts the ciliary muscle opening the trabecular meshwork via M3 receptors ✓
- B Inhibits carbonic anhydrase reducing aqueous production
- C Blocks alpha-1 receptors decreasing episcleral venous pressure
- D Stimulates beta-2 receptors reducing aqueous humor secretion
Correct answer: A. Contracts the ciliary muscle opening the trabecular meshwork via M3 receptors
Explanation
Pilocarpine is a direct muscarinic agonist. It contracts the sphincter pupillae causing miosis and pulls the iris away from the drainage angle. It also contracts the ciliary muscle, opening the trabecular meshwork to facilitate aqueous humor outflow. Both actions relieve angle closure. It does not affect carbonic anhydrase or adrenergic receptors.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.