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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: acetazolamide (a set a ZOLE a mide)
Brand name(s): DIAMOX
GENERIC: available FAMILY: Drugs for Glaucoma
Find the drug label by searching at DailyMed.

Generic drug name: methazolamide (meth a ZOLE a mide)
Brand name(s): NEPTAZANE
GENERIC: available FAMILY: Drugs for Glaucoma
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

These drugs caused fetal harm in animal studies, including limb defects in developing fetuses. Because of the potential for serious adverse effects to the fetus, these drugs should not be used by pregnant women.

Breast-feeding Warning

No information is available from either human or animal studies. However, it is likely that these drugs are excreted in human milk, and because of the potential for adverse effects in nursing infants, you should not take these drugs while nursing.

Facts About This Drug [top]

Acetazolamide and methazolamide are oral drugs used to treat glaucoma. These drugs belong to the carbonic anhydrase inhibitor family of medications that lower the pressure in the eye and thus improve vision in patients with glaucoma. Acetazolamide is also used to treat altitude sickness and to supplement other drugs used for seizure disorders such as epilepsy. In the past, acetazolamide was used as a diuretic (water pill) to treat high blood pressure, but it is outdated for this use because...

Acetazolamide and methazolamide are oral drugs used to treat glaucoma. These drugs belong to the carbonic anhydrase inhibitor family of medications that lower the pressure in the eye and thus improve vision in patients with glaucoma. Acetazolamide is also used to treat altitude sickness and to supplement other drugs used for seizure disorders such as epilepsy. In the past, acetazolamide was used as a diuretic (water pill) to treat high blood pressure, but it is outdated for this use because more effective drugs are now available.[1],[2] Methazolamide is used long-term for open-angle glaucoma. It may be used temporarily before surgery for angle-closure (narrow-angle) glaucoma. Studies of methazolamide to control essential tremor are not yet conclusive.[3]

These drugs are cousins of sulfa drugs and thiazide diuretics, having the potential for the same adverse effects but no action against bacteria. Deaths have occurred, although rarely, due to severe reactions to sulfa drugs. If signs of hypersensitivity or other serious reactions occur, discontinue use of this drug.[4]

This family of drugs may cause kidney stones and gouty arthritis. They may also lower your body’s ability to fight infection by impeding the proper functioning of bone marrow. Older people with decreased kidney function need to be cautious when taking these drugs. These drugs may also reduce the amount of potassium in your body. To compensate for this loss, eat foods high in potassium. Many individuals cannot tolerate the adverse effects of this family of drugs for a prolonged period of time.[2]

Acetazolamide has caused a few cases of hives, fever, blood cell disorders, and kidney problems.[5] Stop taking the drug and call your doctor if you experience any of these reactions.

Methazolamide can upset the gastrointestinal tract and severely deplete your levels of calcium, potassium, and other minerals. Unfortunately, stopping methazolamide does not always reverse the damage to bone marrow.[6] Those with liver disease are at an increased risk of serious liver problems when using methazolamide.[7]

Before You Use This Drug [top]

Do not use if you have or have had:

  • allergies to acetazolamide, sulfas, or thiazide diuretics
  • acidosis, hyperchloremic type
  • adrenal gland failure
  • kidney or liver problems
  • very low potassium or sodium levels
  • diabetes

Tell your doctor if you have or have had:

  • pregnancy or are breast-feeding
  • allergies to carbonic anhydrase inhibitors
  • adrenal gland problem (Addison’s disease)
  • diabetes
  • gout
  • hyperchloremic acidosis
  • low blood level of sodium
  • low blood level of potassium
  • kidney or liver problems, including kidney stones
  • liver problems, including cirrhosis
  • emphysema or other chronic lung disease

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Do not use more often or in a higher dose than prescribed. Do not stop taking this drug suddenly. Your doctor must lower your dose gradually. Until you know how you react to this drug, do not drive or perform other activities requiring alertness. This drug may cause drowsiness, dizziness, lightheadedness, and/or tiredness.
  • To help prevent kidney stones, drink at least six to eight glasses (eight ounces each) of fluids each day.
  • Caution diabetics: This drug may elevate blood and urine sugar levels.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take with food or milk.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.
  • Take with food to decrease stomach upset.
  • Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Do not allow to freeze.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

aspirin, AZOPT, brinzolamide, cyclosporine, dorzolamide, ECOTRIN, ESKALITH, GENUINE BAYER ASPIRIN, HIPREX, lithium, LITHOBID, LITHONATE, methenamine, NEORAL, quinidine, SANDIMMUNE, TOPAMAX, topiramate, TRUSOPT, UREX.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • bloody or dark (acetazolamide) urine, difficult, painful, or burning urination; or sudden decrease in amount of urine
  • bloody or black, tarry stools
  • clumsiness, unsteadiness
  • convulsions
  • pale stools (acetazolamide)
  • yellow eyes or skin (acetazolamide)
  • dry mouth or increased thirst
  • irregular heartbeat or weak pulse
  • mood or mental changes
  • muscle cramps, pain, or weakness
  • nausea or vomiting
  • nearsightedness
  • unusual tiredness or weakness
  • fever and sore throat
  • unusual bruising or bleeding
  • hives, itching, sores, or skin rash
  • mental confusion or depression
  • trouble breathing or shortness of breath
  • ringing or buzzing in ears
  • tremors in hands or feet
  • vision changes
  • confusion
  • lower back pain
  • severe muscle weakness or trembling
  • shortness of breath

Call your doctor if these symptoms continue:

  • constipation
  • diarrhea
  • dizziness or lightheadedness (methazolamide)
  • drowsiness
  • general feeling of discomfort or illness
  • headache
  • increased frequency of urination or amount of urine
  • increased sensitivity of eyes to sunlight
  • appetite loss
  • loss of taste and smell
  • metallic taste in mouth
  • nausea or vomiting
  • numbness, tingling, or burning in hands, fingers, feet, toes, mouth, tongue, lips, or anus
  • weight loss
  • impotence[8]

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • complete blood count
  • blood electrolyte (sodium, potassium) tests
  • platelet count
  • tests of kidney function and kidney stone formation

last reviewed January 31, 2021