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Home / Travel Health / Altitude Sickness / Diamox (Acetazolamide)

Diamox (Acetazolamide)

Buy Diamox (Acetazolamide) tablets for altitude sickness

  • Pack of 112 Acetazolamide 250mg tablets
  • Box of Acetazolamide (Diamox) tablets with bottle
  • Bottle of Acetazolamide 250mg tablets
5 3 patient review(s) review
Dr. Kok Ching Ng
Content reviewed on 29-08-20 Dr. Kok Ching Ng
Prescribing Doctor
MBBS, MRCP Diploma (GMC Reg: 2378125)

Diamox is under review by our doctors and orders have been currently stopped. For more information on alternative treatments to altitude sickness, please visit our altitude sickness information page, or for further advice on travel health please head to our dedicated travel health page.

What is Diamox (acetazolamide)?

Diamox (acetazolamide) is a prescription medication, which contains the active ingredient acetazolamide. It is not officially licensed as a treatment for altitude sickness but it can be prescribed by a doctor for the purpose of preventing the condition if it is deemed appropriate to do so. Many people have used Diamox successfully to help prevent altitude sickness, but it is important to note that the medication should not be used as an alternative to appropriately preparing for ascending to high altitudes nor as an alternative for acclimatisation.

How does Diamox (acetazolamide) work?

Diamox contains the active ingredient acetazolamide, a carbonic anhydrase inhibitor and diuretic. Acetazolamide works to affect the acidity of the blood, which helps to reduce the possibility of symptoms like headaches. It also produces bicarbonate, which helps in the process of removing adequate amounts of water from the blood through urine. This means there is a lower level of fluid around the brain, heart and lungs, aiding breathing. By having this effect on the body, acetazolamide can help to prevent symptoms of altitude sickness occurring. The active ingredient is also used to treat glaucoma.

What are the benefits of Diamox (acetazolamide) tablets?

Even in its mildest form, altitude sickness can have a negative impact on what should otherwise be an enjoyable experience. In severe cases, it can put your health at serious risk, sometimes requiring hospitalisation.

Acetazolamide (Diamox) can help to prevent altitude sickness from occurring and is also beneficial in treating mountain sickness. Thus, it can be highly beneficial to people planning on ascending to high altitudes. It is important to take appropriate precautionary measures such as acclimatisation and avoiding arriving directly to areas of high altitude.

Actazolamide (Diamox) is available in 250mg tablet form, meaning it is very easy to store and take while on the move.

How do I take Diamox (acetazolamide) tablets?

The recommended dose is 125 mg twice a day.1 Half a 250mg tablet should be swallowed whole with a glass of water, preferably alongside a meal. It is advised to start acetazolamide 2-3 days before you begin your ascent2. It can be discontinued 2-3 days after reaching the highest sleeping altitude, or once descent has begun. You should follow the course of treatment prescribed to you and never increase or decrease your dosage without discussing it with a doctor first.

You should endeavour to use it as close to the instructions listed in the patient information leaflet attached with the medication.

Please note that it is essential to follow the normal methods of altitude sickness prevention even if you are taking medication for it. It is important to allow your body the time it needs to acclimatise to new altitudes.

In what dosages are Diamox (acetazolamide) tablets available?

Acetazolamide tablets are only available in the form of a 250mg tablet. Your doctor will be able to tell you more about the dosage and what to do if you think you have taken too much.

What side effects occur with Diamox (acetazolamide) tablets?

There is a small risk of side effects with this medication, as is the case with any prescription medication. These rarely occur but if they do whilst using this medication, you may experience:

  • Vomiting
  • Nausea
  • Dizziness
  • Rash

Such effects should only be mild and will not last for very long. More serious effects, such as an allergic reaction, will require urgent medical attention.

A full list of side effects can be found in the Diamox patient information leaflet.

What are the precautions/interactions of Diamox (acetazolamide)?

Acetazolamide is clinically proven to be a safe medication with a relatively low risk of side effects. It is important to bear in mind that though acetazolamide can be prescribed by a doctor to help prevent altitude sickness, it has not been strictly licensed for this purpose. Diamox (acetazolamide) should never be used as an alternative to methods of acclimatisation. As a prescription medication, there are some contraindications to its use.

This medication should not be taken by anyone who:

  • Has an allergy or hypersensitivity to acetazolamide or any other ingredient contained in it.
  • Is pregnant or breastfeeding.
  • Has low blood potassium or sodium levels, problems with your kidneys or liver, have Addison's disease or suffer from gout or lung problems.

For further information about the side effects, interactions and precautions of using Diamox, please refer to the helpful patient leaflet. This is included in your medication's packet. It is also available in PDF form to download at the bottom of this page.

Can I still buy Diamox (acetazolamide) tablets online safely?

Diamox, the brand, has been discontinued. It is available as Acetazolamide which is the active ingredient found in Diamox. You can purchase Acetazolamide from our website. To receive your tablets, you will first need to complete a brief online consultation. This only takes a few minutes and allows our doctors to assess your medical history, and assess if this medication is a suitable treatment for you. Once your prescription has been prepared, your medicine will be ready for express dispatch from our pharmacy. If you have any queries, please do not hesitate to speak to our friendly UK customer service team.

Treatment Information
Treatment Information
Product Name: Acetazolamide
Active Ingredient(s): Acetazolamide
Manufacturer: Mercury Pharma
Description: Acetazolamide is a prescription treatment used to effectively prevent the symptoms associated with altitude sickness
Exemption: Subject to medical prescription
Administration: Oral
Presentation: Tablets
Available Dosage: 250 mg
Application: Men and women over 18 needing altitude sickness prevention treatment
Posology: Take up to 4 tablets a day, starting 2 days before ascent
Drug class: Carbonic anhydrase inhibitors
Alcohol consumption: Can cause side effects - take caution or avoid alcohol consumption, seek a GP for further advice
When breastfeeding: Caution is recommended, ask your doctor and read the leaflet thoroughly for each treatment
When pregnant: Caution is recommended, ask your doctor and read the leaflet thoroughly for each treatment
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Current reviews for the treatment Diamox (Acetazolamide)

Rated with 5 based on 3 independent customer reviews

  • Excellent Product Review: very quick and easy 05 Oct
  • Excellent Product Review: Great product many thanks 26 Mar
  • Excellent Product Review: The service was excellent, fast, easy to do and the products were delivered to m... 05 Sep