Method for the management of intraocular pressure

In a method for treating ocular hypertension in a warm-blooded animal responsive to acetazolamide and having ocular hypertension, the improvement consisting of orally administering to the animal an osmotic dosage formulation consisting of a wall of semipermeable cellulose acetate surrounding a compartment containing up to 250 mg of acetazolamide, which is released through a passageway in the wall to the animal in a controlled, and continuous rate, and in a therapeutically effective amount up to 20 milligrams per hour over a prolonged period up to 12 hours to produce effective blood levels for lowering intraocular pressure within the average normal range, said method of acetazolamide administration occurring independent of the pH of the animal, producing a hypotensive effect, a blood plasma acetazolamide concentration that is in a steady, substantially constant state and characterized by a low plasma dosage form index of less than 2.5 as exemplified by the ratio of the maximum to minimum plasma concentration of the acetazolamide, said plasma concentration lower than the plasma level obtained by non-osmotic delivery of acetazolamide while concomitantly equally lowering the intraocular pressure and lessening the incidence of side effects of drowsiness, confusion and paresthesias associated with the administration of acetazolamide.