acetazolamide

Generic Name: acetazolamide (a SEET a ZOLE a mide)

Brand Names: Diamox, Diamox Sequels

What is acetazolamide?

Acetazolamide is a carbonic anhydrase inhibitor. Carbonic anhydrase is a protein in your body. Acetazolamide reduces the activity of this protein.

Acetazolamide is used to treat glaucoma and to treat and to prevent acute mountain sickness (altitude sickness). It is also used as a part of some treatment plans for congestive heart failure and seizure disorders.

Acetazolamide may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about acetazolamide?

Call your doctor immediately if you experience a sore throat, fever, unusual bleeding or bruising, tingling or tremors in your hands or feet, pain in your side or groin, or a rash. These symptoms could be early signs of a serious side effect.

Use caution when driving, operating machinery, or performing other hazardous activities. Acetazolamide may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Avoid prolonged exposure to sunlight. Acetazolamide may increase the sensitivity of your skin to sunlight. Use a sunscreen and wear protective clothing when exposure to the sun is unavoidable.

Who should not take acetazolamide?

Tell your doctor if you have ever had an allergic reaction to a sulfa-based drug such as sulfamethoxazole (e.g., Bactrim, Septra, Gantanol). Acetazolamide is also a sulfa-based drug, and you may have a similar reaction to it.

Before taking acetazolamide, tell your doctor if you

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  are on aspirin therapy,

  
  


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  have liver disease,

  
  


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  have kidney disease,

  
  


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  have heart disease,

  
  


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  have lung disease, or

  
  


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  have a hormonal disease.

  
  

You may not be able to take acetazolamide, or you may require a lower dose or special monitoring during treatment if you have any of the conditions listed above.

Acetazolamide is in the FDA pregnancy category C. This means that it is not known whether acetazolamide will harm an unborn baby. Do not take acetazolamide without first talking to your doctor if you are pregnant. Acetazolamide passes into breast milk. It is not known whether acetazolamide will affect a nursing infant. Do not take acetazolamide without first talking to your doctor if you are breast-feeding a baby.

How should I take acetazolamide?

Take acetazolamide exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water. Take acetazolamide with food if it upsets your stomach. Store acetazolamide at room temperature away from moisture and heat.

See also: Acetazolamide dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take only your next regularly scheduled dose. Do not take a double dose of this medication.

What happens if I overdose?

Seek emergency medical attention.

Symptoms of an acetazolamide overdose are not well known, but the following symptoms might be expected: drowsiness, decreased appetite, nausea, vomiting, dizziness, numbness or tingling, shaking, and ringing in the ears.

What should I avoid while taking acetazolamide?

Use caution when driving, operating machinery, or performing other hazardous activities. Acetazolamide may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Avoid prolonged exposure to sunlight. Acetazolamide may increase the sensitivity of your skin to sunlight. Use a sunscreen and wear protective clothing when exposure to the sun is unavoidable.

Acetazolamide side effects

If you experience any of the following serious side effects, stop taking acetazolamide and seek emergency medical attention:

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  an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);

  
  


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  a sore throat or a fever;

  
  


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  unusual bleeding or bruising;

  
  


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  side or groin pain;

  
  


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  tingling or tremors in your hands or feet; or

  
  


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  a rash.

  
  

Other, less serious side effects may be more likely to occur. Continue to take acetazolamide and talk to your doctor if you experience

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  decreased appetite, nausea, vomiting, constipation, diarrhea, or changes in taste;

  
  


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  drowsiness, dizziness, fatigue, or weakness;

  
  


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  nervousness or mild tremor;

  
  


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  headache or confusion;

  
  


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  increased sensitivity of the skin to sunlight;

  
  


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  worsening gout;

  
  


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  loss of blood sugar control (if you are diabetic);

  
  


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  ringing in your ears or hearing problems; or

  
  


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  changes in your vision.

  
  

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.

Acetazolamide Dosing Information

Usual Adult Dose for Edema:

250 to 375 mg oral or IV once a day.

When continued acetazolamide therapy for edema is desired, it is recommended that every second or third dose be skipped to allow the kidney to recover.

Usual Adult Dose for Acute Mountain Sickness:

Oral tablet: 125 to 250 mg orally every 6 to 12 hours.
-or-
SR capsule: 500 mg orally every 12 to 24 hours.

The maximum recommended dose is 1 gram/day.
For rapid ascent, higher doses are beneficial for preventing acute mountain sickness beginning 24 to 48 hours before ascent and continuing for 48 hours while at high altitude.

Usual Adult Dose for Glaucoma:

Open-angle Glaucoma:

tablet or IV injection: 250 mg 1 to 4 times a day.
- or-
SR capsule: 500 mg once or twice a day.

Closed-angle glaucoma:

250 to 500 mg IV, may repeat in 2 to 4 hours to a maximum of I gram/day.

Usual Adult Dose for Seizure Prophylaxis:

8 to 30 mg/kg/day in 1 to 4 divided doses. Do not exceed 1 gram per day.

If this patient is already taking other anticonvulsants, the recommended starting dosage is 250 mg once a day. If acetazolamide is used alone, most patients with good renal function respond to daily doses ranging from 375 to 1000 mg. The optimum dosage for this patient with renal dysfunction is not known, and will depend on this patient's clinical response and tolerance.

Acetazolamide is primarily used for the treatment of refractory epilepsy in combination with other drugs. Although it may be useful in partial, myoclonic, absence, and primary generalized tonic-clonic seizures uncontrolled by other marketed agents, it has been inadequately studied by current standards for these conditions.

Usual Pediatric Dose for Glaucoma:

>= 1 year:

Oral: 8 to 30 mg/kg/day or 300 to 900 mg/m²/day divided every 8 hours.
-or-
IV: 20 to 40 mg/kg/day divided every 6 hours.

Maximum dose: 1 gram/day.

Usual Pediatric Dose for Edema:

>= 1 year:

Oral or IV: 5 mg/kg or 150 mg/m² once a day.

Usual Pediatric Dose for Epilepsy:

>= 1 year:

Oral: 8 to 30 mg/kg/day in 1 to 4 divided doses. Maximum dose is 1 gram/day.

Usual Pediatric Dose for Hydrocephalus:

Oral or IV: 20 to 100 mg/kg/day divided every 6 to 8 hours. Maximum dose is 2 grams/day.

What other drugs will affect acetazolamide?

Before taking this medication, tell your doctor if you are taking any of the following medicines:

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  cyclosporine (Sandimmune). Cyclosporine may have more side effects if it is taken with acetazolamide.

  
  


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  primidone (Mysoline). Primidone may not be as effective if it is taken with acetazolamide, and seizure control may be reduced.

  
  


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  diflunisal (Dolobid). Diflunisal may increase both the activity and the side effects of acetazolamide.

  
  


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  aspirin, salsalate (Disalcid, Salflex, Salsitab, others), choline salicylate (Arthropan), magnesium salicylate (Doan's, Magan, Mobidin), and other aspirin-like products (salicylates). These medicines may also interact with acetazolamide, and special monitoring of your therapy may be necessary.

  
  


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  lithium (Lithobid, Eskalith, others). Acetazolamide may decrease the level of lithium in your blood. Special monitoring or a dosage adjustment may be necessary.

  
  

Drugs other than those listed here may also interact with acetazolamide. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.

More acetazolamide resources

• Acetazolamide Side Effects (in more detail)
• Acetazolamide Dosage
• Acetazolamide Use in Pregnancy & Breastfeeding
• Drug Images
• Acetazolamide Drug Interactions
• Acetazolamide Support Group
• 22 Reviews for Acetazolamide - Add your own review/rating

• Acetazolamide Prescribing Information (FDA)


• Acetazolamide Professional Patient Advice (Wolters Kluwer)


• Acetazolamide Monograph (AHFS DI)


• Acetazolamide MedFacts Consumer Leaflet (Wolters Kluwer)


• Diamox Prescribing Information (FDA)


• Diamox Sequels Sustained-Release Capsules MedFacts Consumer Leaflet (Wolters Kluwer)

Compare acetazolamide with other medications

• Edema
• Epilepsy
• Glaucoma
• Hydrocephalus
• Mountain Sickness / Altitude Sickness
• Pseudotumor Cerebri
• Seizure Prevention

Where can I get more information?

• Your pharmacist can provide more information about acetazolamide.

See also: acetazolamide side effects (in more detail)