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Acetazolamide Tablets 250mg

Acetazolamide Tablets 250mg

Pack Size: 28 tablets
RRP: £49.95
Saving: £21.45
Our Price: £28.50
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Age: 18 Years +

Acetazolamide is the generic version of the branded treatment Diamox (discontinued). It is prescribed by The Independent Pharmacy Online Doctor to prevent and treat altitude sickness in those ascending above 2,500 - 3,000m. 

Pharmacist Tip

You should take a trial dose of half a tablet (125mg acetazolamide) for 2 - 4 days before you leave for your trip to ensure you do not have experience any adverse effects. 

Acetazolamide 250mg tablets (also known as Diamox) are available to buy from The Independent Pharmacy Online Doctor service, following a free consultation, to help to prevent and treat altitude sickness. To find out more about acne and see all the available treatments, see our Online Doctor Altitude Sickness page.

Azetazolamide has several applications but is widely used to prevent or reduce the symptoms of altitude sickness. Azetazolamide can actively reduce the nausea, dizziness, headache and shortness of breath associated with rapid ascents (usually anything above 10,000 feet or 3,048 metres).

Azetazolamide 250mg tablets works to treat altitude sickness by increasing the amount of urine produced, consequently altering the acidity of the blood. This leads to a reduction in fluid in the lungs and around the brain. The result is improved breathing and relief from the symptoms of altitude sickness.

Without medication the symptoms of altitude sickness will usually subside in around 24-48 hours if the proper procedures are followed. Taking Azetazolamide 250mg tablets has been shown to cut recovery time in half (between 12-24 hours).

Taking Azetazolamide will help to decrease the likelihood of experiencing altitude sickness in people who are forced to ascend without the proper acclimatisation. However, Azetazolamide should not be seen as a substitute for acclimatisation. Rapid ascents can still carry dangers with or without Azetazolamide usage.

Sleeping at altitude alters a person’s breathing patterns. It is usually characterised as short, rapid breaths followed by prolonged pauses. This is quite normal and is not considered dangerous. However, it can lead to a poor quality of sleep. Taking Azetazolamide tablets will help improve this pattern of breathing, resulting in a better quality of sleep.

Azetazolamide used to be known as Diamox tablets. However, the brand Diamox has been discontinued. The medication has since been rebranded as Azetazolamide tablets, which was the same active ingredient found in Diamox. Azetazolamide belongs to a category of medicines called diuretics. A diuretic is any substance that increases the production of urine, thus promoting the excretion of water from the body. Azetazolamide is manufactured by MercuryPharma. The tablet itself is white, round and convex with “FW 147” marked on one side. The other side of the tablet is scored into quarters. Azetazolamide is a prescription only medicine (POM). 

The dose of Acetazolamide will depend on how severe your mountain sickness is and the symptoms you are experiencing. You or a member of your group will need to decide on the most appropriate treatment. If you have a doctor or other healthcare professional on your trip, you should seek their advice. 

1. For the treatment of mild early acute mountain sickness (headache, fatigue, lightheadedness, difficulty with sleep): Acetazolamide 250mg (one tablet) twice daily until symptoms resolve when planned ascent can be resumed.

2. Where rapid ascent without proper acclimatisation cannot be avoided: Acetazolamide 250mg (one tablet) twice daily, started the day before ascent or as soon as possible after starting to ascend and continue for 2-3 days after final altitude is reached.

3. For disturbed breathing pattern during sleep: Acetazolamide 125mg (half a tablet) twice daily. Continue until descent to an altitude where sleep is no longer a problem.

Remember: even if you take Acetazolamide, it is still important to properly acclimatise. You should never ascend further until your symptoms have completely gone and you are properly acclimatised to your current altitude. Do not use Acetazolamide to push through the symptoms of altitude sickness and continue to climb, this is extremely dangerous and can be fatal. 

Each tablet contains the active ingredient acetazolamide 250mg.

It also contains: lactose monohydrate, corn starch, gelatin, glycerin, water, talc,sodium starch glycolate type A potato, magesium stearate.

The following side effects can occur when taking Acetazolamide:

Dizziness, lightheadedness, and an increased amount of urine, blurred vision, dry mouth, drowsiness, loss of appetite, stomach upset, headache and tiredness.

These side effects are most likely at the start of treatment as your body gets used to the medicine. 

Tell your doctor immediately if any of these very unlikely but serious side effects occur: increased body hair, hearing loss, ringing in the ears, unusual tiredness, persistent nausea/vomiting, severe stomach/abdominal pain.

Seek immediate medical attention if any of these unlikely but very serious side effects occur: easy bleeding/bruising, fast/irregular heartbeat, signs of infection (e.g., fever, persistent sore throat), mental/mood changes (e.g., confusion, difficulty concentrating), severe muscle cramps/pain, tingling of the hands/feet, blood in the urine, dark urine, painful urination, yellowing of the eyes/skin.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include:blisters/sores in the mouth, rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

If you experience any adverse effects from taking Acetazolamide it is important your trip doctor know immediately. In a medical emergency you should contact the emergency services or go straight to a hospital or medical centre.


Acetazolamide is not suitable for use if you:

  • are allergic or sensitive to or have had a bad reaction to sulphonamides in the past.
  • are elderly.
  • have adrenal gland problems.
  • have chronic obstructive pulmonary disease.
  • have closed angle glaucoma.
  • have had kidney stones.
  • have kidney or liver problems.
  • have lung problems.
  • have metabolic problems.
  • have salt and water imbalances.
  • have urinary problems.
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The Independent Pharmacy is an online pharmacy and online doctor service is owned and operated by ABSM Healthcare Ltd (Company Reg. 08515600) and Red Label Medical Ltd (Company Reg. 08676338). All information that appears on this website is intended for information purposes only and should be used to supplement, not replace, your relationship with your local healthcare professionals. You should consult your doctor if you think you may have a health problem or before you start taking a new medicine. Please ensure you always read the information leaflets supplied with any medicinal products.For more information see our policies and terms and conditions at the bottom of every page. © 2014 ABSM Healthcare Ltd. All rights reserved.
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