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Home / Travel Health / Altitude Sickness / Diamox (Acetazolamide)
Manufactured by mercurypharma

Diamox (Acetazolamide)

Diamox (Acetazolamide) available online to treat altitude sickness

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You can buy Diamox (Acetazolamide) prescription medication online to successfully prevent altitude sickness and the potentially dangerous symptoms caused by the condition. Using the ingredient acetazolamide, these treatment tablets work by increasing the acidity of the blood and stimulating ventilation inside the body, effectively increasing the amount of oxygen into the blood. Consequently this can help to reduce the effects of lack oxygen at high altitudes, preventing symptoms such as nausea. Diamox can be taken alongside acclimatisation methods to give you the best chance possible at preventing altitude sickness.

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.
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How to buy Diamox online?

Diamox (acetazolamide) altitude sickness tablets are available to buy online at OnlineClinic in the recommended dosage of 250mg. You can order this medication in a single pack containing 28 tablets. Purchasing this treatment online from OnlineClinic will ensure that you can completely avoid the inconvenience of attending a face-to-face doctor's appointment. Diamox pills are highly effective in preventing and treating altitude sickness. You can buy extra packs of Diamox tablets quickly and securely online by using our repeat ordering process. A useful reminder service will prompt you to order more tablets when they're needed.

This altitude sickness treatment can be ordered online at OnlineClinic after filling out a quick and simple online consultation form. Once this is approved, your medication will be delivered to you via our fast and completely free next day delivery service.

What is Diamox?

When individuals climb high altitudes too quickly, the possibility exists that altitude sickness might affect them. This presents itself in a number of ways, including headaches and breathlessness, and can lead to serious health concerns, such as pulmonary and cerebral oedema. Diamox (Acetazolamide) can assist the body to compensate for the change in altitude and reduce the chances that hypoxia, deprivation of oxygen, develops and altitude sickness grows any worse. It can be used as a preventative treatment as well as for immediate assistance.

Short facts about Diamox
How to take

Take 1 tablet twice a day with plenty of fluids. Dosages will vary for more serious cases.

How it works

Acetazolamide (the active ingredient) increases oxygen levels in the blood by stimulating ventilation.


Diamox compensates for changes in altitude and prevents the development of hypoxia and oxygen deprivation. Diamox can be used as both a preventative treatment and for immediate assistance.


You can buy Diamox pills at OnlineClinic in the recommended dose of 250 mg.

Side effects

Side effects aren't very common, but can potentially include blurred vision, frequent urination and a slight taste alteration.

How does Diamox work?

Diamox, using its active ingredient acetazolamide, works within the body by stimulating the kidneys to produce bicarbonate. This makes the amount of bicarbonate excreted through urine increase, while making the blood more acidic. In turn this stimulates ventilation, which increases the levels of oxygen in the blood. As hyperventilation at high altitudes is in response to decreased oxygen levels, which causes more bicarbonate to be produced for the same effect, acetazolamide acts as a prophylactic to this process. Altogether it makes avoiding altitude sickness easier.

How to take Diamox?

Listed below are some helpful instructions, with regards to how you should take Diamox tablets:

  • Diamox, and the generic version Acetazolamide, should only ever be taken as prescribed by a doctor, but general guidelines suggest that for treatment of mild altitude sickness one 250mg taken twice daily should be enough when used preventatively.
  • For more serious cases or depending on the altitude intended on climbing, Diamox dosages will vary.
  • It's extremely important that you familiarise yourself with the medication and your destination before using treatment and ascending.
  • Plenty of fluids are required when using this medication, as it does make the blood slightly more acidic in order to help prevent dehydration.


Diamox tablets are available to buy at OnlineClinic in a dose of 250mg. This is the recommended dosage according to our doctors. You can order this medication in a single pack of 28 tablets.

Side effects and precautions

All prescription medications can cause side effects, although generally they are mild and only experienced for short periods of time. Common Acetazolamide side effects may include a tingling sensation in the fingers and toes, blurred vision, slight taste alteration and frequent urination. If any of these potential side effects persist you should consult your doctor about the interaction you're experiencing. More serious side effects can possibly include increasing the risk of developing kidney stones. If this is the case you should seek medical attention immediately.

Before you decide to buy Diamox there are some precautions that should be considered:

  • Diamox tablets should be taken with caution if you are elderly or have a decreased kidney or liver function, difficulty passing urine, breathing difficulties, or a history of kidney stones.
  • Diamox tablets should not be taken if you have severe kidney or liver disease, underactive adrenal glands, low levels of potassium or sodium, or high levels of chloride in the blood.
  • You should not buy Diamox during pregnancy.

Treatment Information

Treatment Information
Product Name: Diamox
Active Ingredient(s): Acetazolamide
Manufacturer: Mercury Pharma
Administration: Oral
Presentation: Tablets
Available Dosage: 250 mg
Exemption: Subject to medical prescription
Application: Men and women over 18 needing altitude sickness prevention treatment
Posology: Take up to 4 tablets a day, starting 2 days before ascent
Description: Diamox is a prescription treatment used to effectively prevent the symptoms associated with altitude sickness
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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