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Home / Travel Health / Altitude Sickness / Diamox


Buy Diamox (acetazolamide) online to treat altitude sickness

  • Pack of 112 Acetazolamide 250mg tablets
  • Box of Acetazolamide (Diamox) tablets with bottle
  • Bottle of Acetazolamide 250mg tablets
4.3 8 patient review(s) review
Dr. Sarah Donald
Dr. Sarah Donald Clinical Lead
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.

How does Diamox work?

Acetazolamide, the active ingredient in Diamox is a carbonic anhydrase inhibitor as well as a diuretic. This treatment aims to influence blood acidity levels. By doing this it can reduce the risk of symptoms such as headaches.

In addition to influencing blood-acidity levels, it also produces bicarbonate, which gives it its diuretic effect, thereby ensuring that the water levels in blood remain at a healthy level. Both these actions don't just help to reduce the mild discomforts associated with this condition but can also reduce the risk of a patient developing more serious complications.

Who should use Diamox?

Although generally safe to use, this can't be taken safely by everybody. People who should not use Diamox are those who are allergic or sensitive to the ingredient acetazolamide or any of the other ingredients contained in this medication. It's also unsuitable for pregnant or breastfeeding women to use, those with low blood potassium or sodium levels, patients with liver or kidney conditions or who have been diagnosed with Addison's disease, suffer from gout or have lung problems.

When completing your online consultation with 121doc, you should make sure that you provide us all the health information that is asked, as this will provide our doctor with the suitable data to make the best recommendation for you. our doctor will also want to be sure that you'll be using this treatment safely and not as an alternative to traditional acclimatisation measures.

How do you take this medication?

This medicine is available in a 125mg or a 250mg dose. The tablets should be swallowed whole, with a glass of water alongside a meal. The dosage that will be prescribed to you will depend on your individual needs and current health, although the traditional recommendation will be up to a maximum of four tablets a day. As it is a preventative treatment, you'll likely have to start taking your acetazolamide tablets a couple of days before you start ascending.

It is essential that you follow traditional methods for avoiding altitude sickness and that you don't change your dose without speaking to your doctor first.

What are the side effects of Diamox?

All prescription medications have a minor risk of side effects, but it doesn't mean that they will appear in everyone who uses this treatment. Side effects that have been reported are nausea, vomiting, dizziness or rash, but luckily these are mild and shouldn't be lasting. You should, however, be aware that one of the rare side effects of this treatment is an allergic reaction, for which you will need to seek immediate medical help.

How to order online

You can prepare for your climb by ordering Diamox safely from 121doc. Here we ask all our patients to complete a completely free and confidential consultation form, as this will allow our licensed doctor to provide a prescription based on your individual needs. This means that our doctor may choose not to provide you with a prescription if this is a safer option. If a prescription is issued, it will be sent straight to our pharmacy, where a registered pharmacist will dispense it. It will then be packaged and dispatched via secure courier service for next day delivery. All orders include a free consultation and there is no additional charge for delivery.

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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