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 (as in glaucoma). They may also be used to decrease abnormal fluid leakage from blood vessels in the retina (e.g. retinitis pigmentosa). These pills are very effective and may be used along with eye drops to lower the eye pressure. The two most common pills used are Diamox (acetazolamide) and Neptazane (methazolamide).
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.
It may be helpful to take potassium supplements (e.g. banana) while on CAI to prevent low potassium levels in the blood. Low serum potassium may cause muscle cramps and weakess, abdominal cramps, palpitations, faintness from low blood pressure, and depression.
The dosage of CAI may be reduced in patients with reduced kidney function (see table below). CAI may not be used in advanced cases of liver cirrhosis.
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), phenytoin (Dilantin), carbamazepine, primidone, and lithium. Caution should be used when taking metformin for diabetes; CAI may increase the risk of lactic acidosis. Be sure to notify your doctor if you are taking any of these medicines.
How to adjust the dosage in kidney failure?
The table below shows how to adjust dosage of acetazolamide (Diamox) in the setting of kidney disease.
| Glomerular Filtration Rate (GFR) in mL/min | Dosage |
| 20-50 | 250 mg up to 4 times a day |
| 10-20 | 250 mg up to 2 times a day |
| <10 or on dialysis | 250 mg daily or 3 times a week |
reference: https://kidneydiseaseclinic.net/renaldrugs/Acetazolamide.php
For a telemedicine consultation with Dr Pautler, please send email request to spautler@rvaf.com. We accept Medicare and most insurances in Florida. Please include contact information (including phone number) in the email. We are unable to provide consultation for those living outside the state of Florida with the exception of limited one-time consultations with residents of the following states: Alabama, Arkansas, Connecticut, Georgia, Minnesota, and Washington.
Copyright © 2022 Designs Unlimited of Florida. All Rights Reserved.