Brimonidine 0.2% eye drops exert their IOP-lowering effect primarily through which mechanism?

• A Beta-1 receptor blockade reducing aqueous production
• B Carbonic anhydrase inhibition in the ciliary processes
• C Prostaglandin receptor agonism increasing uveoscleral outflow
• D Alpha-2 adrenoreceptor agonism reducing aqueous production and increasing uveoscleral outflow ✓

Explanation

Brimonidine is a selective alpha-2 adrenoreceptor agonist. Its dual mechanism includes: (1) reduced aqueous humour production by inhibiting adenylyl cyclase in the ciliary epithelium, and (2) increased uveoscleral outflow. It crosses the blood-brain barrier and may also provide neuroprotection. It is contraindicated in infants and young children due to CNS depression (apnoea, bradycardia).

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.