A known diabetic patient presents within six hours of an acute primary angle-closure attack with IOP of 56 mmHg. The cornea is edematous. Which IOP-lowering measure is CONTRAINDICATED in this patient?

• A Intravenous mannitol 20%
• B Topical timolol
• C Intravenous acetazolamide
• D Oral glycerol 50% ✓

Explanation

Oral glycerol is metabolized in the body to glucose, causing significant hyperglycemia, so it is avoided in diabetics; it may also cause nausea and vomiting, which is a problem in an acute painful eye. Mannitol given intravenously is the hyperosmotic agent of choice here because it is not metabolized to glucose. Acetazolamide and topical timolol are safe and form part of standard initial therapy alongside pilocarpine once IOP falls below about 40 mmHg.

Reference: Khurana's Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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