Retinal - Macular Disorders

Carbonic Anhydrase Inhibitors
(Diamox and Methazolamide)

by Scott Pautler, MD

What are carbonic anhydrase inhibitors (CAI)?

CAI medicines are sometimes prescribed to lower the pressure in the eye either to control pain or to decrease the chances of damage to the eye from high pressure. These pills are very effective and may be used along with eye drops to lower the eye pressure.

What side effects might be encountered?

While you are taking these medicines, you may notice a tingling sensation in the fingers, toes, or lips; an altered sense of taste; a loss of appetite; drowsiness; a “washed out” feeling; or an increase in urination. These are not allergic reactions, but should be reported to the doctor if they become bothersome.

Only rarely do severe reactions occur. Be sure to report hives, skin rashes, gout, allergy to sulfa antibiotics, kidney stones, kidney failure, mental depression, liver failure, blood in stool or mouth, easy bruising, or anemia.

What other medicines might interact with CAI?

Other drugs rarely interact with CAI and an adjustment in dosage is sometimes needed. CAI may increase the effect of diuretics (HCTZ, lasix, bumex, etc.), high-dose aspirin, and quinidine. CAI may increase the effect of digoxin (lanoxin), primidone, and lithium. Be sure to notify your doctor if you are taking any of these medicines.