Acetazolamide: Uses, Doses, Side Effects, and Practical Tips

Acetazolamide is an old but useful medicine that fights fluid and pressure problems by blocking carbonic anhydrase. Doctors prescribe it for glaucoma, altitude sickness, certain epilepsies, and some types of edema. Here are the basics you need to know so you can use it safely and understand common issues.

How acetazolamide works and when to use it

It lowers production of bicarbonate and decreases fluid secretion in the eye and other tissues, which lowers pressure. Typical uses include: glaucoma (reduces intraocular pressure), acute mountain sickness (helps breathing and symptoms), idiopathic intracranial hypertension, adjunctive therapy for some seizure types, and edema from metabolic alkalosis.

Dosage, side effects, and precautions

Adult dosing often starts at 250–500 mg per day, given as a single or divided dose; some conditions need 1,000 mg daily under supervision. Kids need weight-based dosing and you should follow the pediatrician's plan. Common side effects are tingling in the hands or feet, taste changes, frequent urination, stomach upset, and tiredness. Major concerns include metabolic acidosis, low potassium, kidney stones, and worsening liver or kidney disease. Your doctor may check blood electrolytes and kidney function within a few days to weeks after starting the drug. Acetazolamide can interact with aspirin (salicylates), lithium, certain anticonvulsants, and diuretics; mention all drugs and supplements you take. Avoid use in late pregnancy and tell your doctor if you plan to breastfeed.

If you use it for altitude sickness, start a dose a day before ascent and continue for 48 hours at altitude; it reduces symptoms and helps oxygenation. Store at room temperature away from moisture. If you miss a dose, take it as soon as you remember unless it's almost time for the next dose. If you have a sulfa allergy, tell your doctor — some people react to acetazolamide. Ask your doctor about routine labs and whether acetazolamide is right for your condition.

Expect a baseline BMP: electrolytes (sodium, potassium), bicarbonate, BUN, and creatinine. A low bicarbonate or rising creatinine means stop or adjust dose. Red flags—go to ER or call doctor if you have severe shortness of breath, fainting, chest pain, severe rash, high fever, or blood in urine. People with reduced kidney function clear acetazolamide slowly; doctors may avoid it or use much lower doses. During dialysis the drug may be removed; discuss timing with the nephrology team.

Avoid heavy exercise, hot environments, and alcohol while starting the medicine because dehydration and electrolyte loss increase risk. Available forms include oral tablets and IV for hospital use. The tablet is common for outpatient needs. Generic acetazolamide is inexpensive, but check prices and insurance coverage. Never buy from unknown online sellers without a prescription.

Can it cause weight loss? Some people lose water weight due to diuresis; this is not fat loss. How fast does it work? For altitude sickness relief often within 24 hours; eye pressure changes may take days. Talk with your provider before stopping the drug; abrupt changes can cause problems. Always.