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Acetazolamide

  • You should not drive or operate machinery if you feel sleepy after taking this medicine.
  • Acetazolamide is not generally recommended for long-term use.

About acetazolamide

Type of medicineCarbonic anhydrase inhibitor
Used forGlaucoma
Some types of epilepsy
Fluid retention
Also calledDiamox®
Diamox® SR
Available asTablets, modified-release capsules and injection

Acetazolamide works by stopping the action of a chemical in the body called carbonic anhydrase. As a result, the amount of some salts in the body are reduced and this promotes a loss of fluid from the body.

Acetazolamide reduces the amount of fluid produced in the eye and this helps reduce the high pressure present in glaucoma.

Acetazolamide can also be useful in some types of epilepsy alongside other medicines.

Before taking acetazolamide

Before taking acetazolamide make sure your doctor or pharmacist knows:

  • If you are pregnant, trying for a baby or breast-feeding.
  • If you have breathing problems.
  • If you know you have low potassium or sodium, or high levels of acid in your blood.
  • If you have liver or kidney problems, or trouble passing urine.
  • If you have a type of glaucoma called chronic non-congestive angle-closure glaucoma.
  • If you have diabetes mellitus.
  • If you have problems with your adrenal glands such as Addison's disease.
  • If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
  • If you have ever had an allergic reaction to this or any other medicine. This is particularly important if you are allergic to sulphonamide antibiotics.

How to take acetazolamide

  • Before starting this treatment, read the manufacturer's printed information leaflet from inside the pack.
  • Take acetazolamide exactly as your doctor has told you. Your dose will depend on what you are being treated for.
  • If you have been given the modified-release capsules of acetazolamide (Diamox® SR), swallow these whole with a drink of water. They should not be chewed.
  • Try to take acetazolamide at the same time(s) each day to avoid missing any doses.
  • If you forget to take a dose, take it as soon as you remember unless it is nearly time for your next dose, in which case leave out the missed dose. Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Keep your regular appointments with your doctor so your progress can be monitored.
  • Acetazolamide is not generally recommended for long-term use but if you need to take acetazolamide over a period of time your doctor will want you to have blood tests.
  • If you have diabetes, acetazolamide may affect your blood sugar levels. Test your urine or blood regularly and speak with your doctor if you notice any changes.
  • If you buy any medicines, check with a pharmacist that they are safe to take alongside acetazolamide.

Can acetazolamide cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common side-effects - these affect less than 1 in 10 people who take this medicineWhat can I do if I experience this
Dizziness, drowsiness, tirednessMake sure your reactions are normal before driving, operating machinery or doing any other jobs which could be dangerous if you were not fully alert
Feeling or being sickEat little and often. Stick to simple or bland foods. Taking the tablets at meal times may help
DiarrhoeaDrink plenty of water to replace any lost fluids
HeadacheAsk your pharmacist to recommend a suitable painkiller
Changes in the way things taste, loss of appetite, flushing, mood changes, thirstiness, tingling feelings, increased need to pass urine, and reduced sexual desireIf any of these become troublesome, speak with your doctor

Some medicines which can be used to treat epilepsy have been associated with a small risk of developing mood changes, distressing thoughts and feelings about suicide. The likelihood of having such thoughts with acetazolamide is not known, but if this happens to you, tell your doctor straight away.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store acetazolamide

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines


  • Never take more than the prescribed dose. If you suspect that you or someone else has taken an overdose of this medicine go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
  • This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
  • Never keep out of date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
  • If you have any questions about this medicine ask your pharmacist.

References

Comprehensive patient resources are available at www.patient.co.uk
© EMIS 2011DocID: 3257DocRef: dils2146Last Reviewed: 15 Mar 2011Version: 24
For the planned review period see the Data Creation and Quality Control Process.
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