Abstract
INTRODUCTION: Acetazolamide-induced uveal effusion and secondary angle closure is a rarely reported but clinically significant phenomenon. The reaction is idiosyncratic and independent of dosage or prior exposure. CASE PRESENTATION: A 52-year-old patient developed severe bilateral uveal effusions, acute angle closure, and myopic shift 24 h after commencing acetazolamide for altitude sickness prophylaxis. The case demonstrates unusually severe posterior involvement after a single prophylactic dose, with dramatic recovery following initiation of intravenous methylprednisolone. CONCLUSION: Given the widespread use of acetazolamide in ophthalmology and other medical disciplines, clinicians must be aware of potentially sight-threatening drug reactions. Prescription of acetazolamide for altitude sickness prophylaxis represents a unique risk, as patients are likely to be travelling to remote destinations. First-time dosing should occur where urgent medical assessment is readily accessible.