Sounds like 'a-set-a-zole-a-mide'

Key points about acetazolamide

  • Acetazolamide is used to treat glaucoma and other conditions like epilepsy.
  • The information provided here is only for glaucoma.
  • Acetazolamide is also called Diamox®.
  • Find out how to take it safely and the possible side effects.
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  • When it's taken for glaucoma, acetazolamide reduces the amount of fluid being made in your eye which lowers the pressure that causes glaucoma.
  • It works by blocking an enzyme called carbonic anhydrase.
  • Acetazolamide is also called Diamox.

In Aotearoa New Zealand, acetazolamide is available as tablets (250 mg).

  • The dose of acetazolamide will be different for different people depending on your response to treatment.
  • The usual dose for simple (open-angle) glaucoma is 1 to 4 tablets daily in divided doses.
  • Always take your acetazolamide exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much acetazolamide to take, how often to take it, and any special instructions.

  • Timing: Take acetazolamide at around the same time each day. If you are taking Diamox several times a day, have at least 4 hours between doses or take as directed by your healthcare provider.
  • Water: Swallow your tablets whole with a large glass of water.
  • Food: You can take acetazolamide with or without food.
  • Take it regularly: Keep taking acetazolamide regularly to control your glaucoma. Acetazolamide is usually needed long-term for open-angle glaucoma because it doesn't cure it. You should continue to take acetazolamide unless you're advised by your doctor to stop. Talk to your healthcare provider before stopping. 
  • Missed dose:  If you forget to take your dose, take it as soon as you remember. But if it is nearly time for your next dose, take the next dose at the right time. Don't take extra doses to make up for a forgotten dose. If you don't know what to do, ask your healthcare provider.

Here are some things to know when you're taking acetazolamide. Other things may be important as well, so ask your healthcare provider what you should know about.

  • Alcohol: Limit alcohol while you're taking acetazolamide, especially when you first start treatment. Drinking alcohol while taking acetazolamide can make you more sleepy.
  • Driving: This medicine may make you sleepy. Be careful when driving or using tools until you know how it affects you.
  • Other medicines: Acetazolamide interacts with some medications, herbal supplements and rongoā Māori, so check with your doctor or pharmacist before starting acetazolamide and before starting any new products.
  • Don't stop taking acetazolamide suddenly: Talk to your doctor before stopping.
  • Monitoring: You may need regular blood tests to check the amount of potassium and sodium in your blood, and to check your liver and kidneys.
  • Pregnancy: Tell your doctor immediately if you become pregnant.
  • Breastfeeding: Talk to your doctor if you would like to start breastfeeding.

Like all medicines, acetazolamide can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine. Let your doctor know if these side effects bother you, there may be other options you can try.

Side effects

What should I do?

  • Tiredness
  • Dizziness
  • These are common when you first start taking acetazolamide.
  • Don't drink alcohol.
  • Tell your doctor if these bother you.
  • Tingling or numb feelings in hands, feet and face
  • This is common.
  • Tell your doctor if this bothers you.
  • Nausea (feeling sick) and vomiting (being sick)
  • Loss of appetite
  • Upset stomach
  • These are less common.
  • Take your tablets with food.
  • Changes in vision
  • Changes in hearing and/or ringing in your ears (tinnitus)
  • Low mood or feeling depressed
  • These are rare.
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of infections happening frequently e.g. fever, chills, sore throat or mouth ulcers
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of liver problems, eg, yellow skin or eyes, dark urine, itching, abdominal pain, pale bowel motions (poo)
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of an allergic reaction, eg, an unusual skin rash, itches, swelling of the face, lips, mouth and tongue or problems breathing. You may also have a fever with these signs.
  • This is rare and serious.
  • Stop taking the medicine.
  • Tell your doctor immediately or ring Healthline 0800 611 116.

Did you know that you can report a medicine side effect to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product.(external link)

For more information on side effects, see the Medsafe consumer information leaflet/s below.


Primary open angle glaucoma(external link) Glaucoma NZ Factsheet


  1. Acetazolamide(external link) NZ Formulary, 2023
  2. Diamox(external link) Medsafe Datasheet, 2023
  3. Acetazolamide(external link) NZ Formulary patient information
  4. Diamox(external link) Medsafe Consumer Medicine Information, 2023
  5. Treatment of glaucoma(external link) NZ Formulary, 2023

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Angela Lambie, Pharmacist, Auckland

Last reviewed: