Acetazolamide is a weak diuretic used to decrease production of aqueous humor in the eye. Hemodialysis patients undergoing ocular surgery may benefit from acetazolamide; however, no pharmacokinetic data are available for this group of patients. We report a patient who received acetazolamide 250 mg every 6 hours after ophthalmic surgery and developed reversible neurological side effects associated with very high plasma concentrations. Using pharmacokinetic analysis, we suggest an alternate administration of acetazolamide for end-stage renal patients.