Question 1

How long before travel should I start taking acetazolamide?

Accepted Answer

Start taking acetazolamide 24 to 48 hours before you begin ascending to high altitude. This allows the medication to reach steady state and for your body to adjust its breathing response before exposure to low oxygen levels.

Question 2

What are the most common side effects of acetazolamide for altitude sickness?

Accepted Answer

The most common side effects are tingling or numbness in fingers and toes (paresthesia), a metallic taste in the mouth, increased urination, and fatigue. These affect more than 1 in 10 people and usually subside after a few days.

Question 3

Can I drink alcohol while taking acetazolamide?

Accepted Answer

It is best to avoid or strictly limit alcohol. Alcohol worsens dehydration, can increase side effects like drowsiness and dizziness, and may mask symptoms of altitude sickness. Both acetazolamide and alcohol increase urination, raising dehydration risk.

Question 4

Is acetazolamide the same as Diamox?

Accepted Answer

Yes, Diamox is a brand name for acetazolamide. The active ingredient is identical. Generic acetazolamide is equally effective and usually less expensive. Both are carbonic anhydrase inhibitors used for altitude sickness prevention.

Question 5

Can I take acetazolamide if I am allergic to sulfa drugs?

Accepted Answer

No. Acetazolamide is a sulphonamide derivative. If you have a known allergy to sulfa antibiotics (e.g., co-trimoxazole) or other sulphonamides, you should not take acetazolamide due to risk of cross-reaction and serious allergic response.

Question 6

Does acetazolamide prevent all forms of altitude sickness?

Accepted Answer

Acetazolamide is highly effective for preventing acute mountain sickness (AMS), but it does not prevent high-altitude pulmonary oedema (HAPE) or cerebral oedema (HACE). It is not a substitute for proper acclimatisation and descent if severe symptoms develop.

Question 7

How often should I take acetazolamide for altitude sickness?

Accepted Answer

The typical dose is 125-250mg every 8 to 12 hours (usually twice daily). For prevention, start 24-48 hours before ascent. For treatment of mild AMS, continue every 8-12 hours until symptoms resolve or you descend.

Question 8

Can I take ibuprofen or paracetamol with acetazolamide?

Accepted Answer

Paracetamol is generally safe to take with acetazolamide for headache. Ibuprofen and other NSAIDs should be used with caution as they may increase the risk of kidney problems, especially when combined with acetazolamide's diuretic effect.

Question 9

Does acetazolamide affect birth control pills?

Accepted Answer

There is no known direct interaction between acetazolamide and oral contraceptives. However, acetazolamide can cause nausea and vomiting, which may reduce absorption of the pill. Use additional barrier contraception if you experience gastrointestinal upset.

Question 10

How long does acetazolamide stay in your system?

Accepted Answer

Acetazolamide has a half-life of about 10-15 hours. It takes approximately 2-3 days for the drug to be completely eliminated from your body after the last dose. Side effects like tingling usually resolve within 24-48 hours after stopping.

Question 11

Can children take acetazolamide for altitude sickness?

Accepted Answer

Acetazolamide is not routinely recommended for children due to limited safety data. In exceptional cases, a specialist may prescribe a weight-based dose (usually 5mg/kg/day in divided doses). Always consult a paediatrician before giving to a child.

Question 12

What should I do if I miss a dose while at altitude?

Accepted Answer

If you miss a dose by less than 2 hours, take it immediately. If more than 2 hours have passed until your next dose, skip the missed dose and take the next one at the usual time. Never double dose. Watch for AMS symptoms carefully.

Question 13

Can acetazolamide cause kidney stones?

Accepted Answer

Yes, long-term use of acetazolamide increases the risk of calcium phosphate kidney stones. This is rare with short courses (a few days) for altitude sickness. Drink plenty of fluids to reduce the risk. Inform your doctor if you have a history of stones.

Question 14

Do I need a prescription for acetazolamide in the UK?

Accepted Answer

Yes, acetazolamide is a prescription-only medicine (POM) in the UK. You cannot buy it over the counter. At Chemist Doctor, our UK-registered clinicians can prescribe it after an online consultation if it is appropriate for your travel plans and medical history.

Product Name	Acetazolamide
Manufacturer	Mercury Pharmaceuticals Ltd
Active Ingredient	Acetazolamide
Administration	Oral tablet
Presentation	White, circular shallow biconvex tablets with quarter breakline
Available Strengths	250mg Standard / 28 tablets
Product Type	POM — Prescription Only
Dosage	Every 8-12 hours for altitude sickness
Suitable for pregnancy?	Do not use
Use with alcohol	Avoid or limit
Link to Patient Information Leaflet	Acetazolamide PIL ↗

Acetazolamide Tablets

Acetazolamide Treatment