Acetazolamide reduces the activity of a protein in your body called carbonic anhydrase. Blocking this protein can help reduce the build-up of certain fluids in the body.

Acetazolamide is used in people with certain types of glaucoma to reduce the amount of fluid in the eye, which decreases pressure inside the eye.

Acetazolamide is also used as a diuretic ("water pill") in people with congestive heart failure, to reduce the build-up of fluid in the body. This build-up is called edema.

Acetazolamide is also used to treat certain types of seizures, and to treat or prevent altitude sickness.

Acetazolamide may also be used for purposes not listed in this medication guide.

You should not use acetazolamide if you are allergic to it, or if you have:

• severe liver disease, or cirrhosis;
• severe kidney disease;
• an electrolyte imbalance (such as acidosis or low levels of potassium or sodium in your blood);
• adrenal gland failure; or
• an allergy to sulfa drugs.

To make sure acetazolamide is safe for you, tell your doctor if you have:

• severe breathing problems;
• angle closure glaucoma; or
• if you also take aspirin in high doses.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Acetazolamide can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

Acetazolamide is not approved for use by anyone younger than 18 years old.

Use Diamox Sequels (Oral) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• blood in urine or stools;
• a seizure (convulsions);
• loss of movement in any part of your body;
• a blood cell disorder--sudden weakness or ill feeling, fever, chills, sore throat, mouth sores, pale skin, feeling tired or short of breath, rapid heart rate, nosebleeds, bleeding gums;
• liver problems--nausea, upper stomach pain or swelling, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
• signs of metabolic acidosis--confusion, vomiting, lack of energy, irregular heartbeats;
• signs of a kidney stone--pain in your side or lower back, blood in your urine, painful or difficult urination; or
• severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

• nausea, vomiting, loss of appetite, diarrhea;
• numbness or tingling, especially in your arms and legs;
• drowsiness, confusion;
• hearing problems, ringing in your ears;
• increased urination; or
• altered sense of taste.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This medicine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Avoid exposure to sunlight or tanning beds. Acetazolamide can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.