Acetazolamide Tablets
Acetazolamide (Diamox) is a prescription medication used for prevention and treatment of altitude sickness, glaucoma, epilepsy, and fluid retention. Available through Chemist Doctor's regulated online service following a consultation with UK-licensed clinicians.
You must complete a short online consultation so that our prescriber can ensure that the treatment is suitable for you.
Assessment
Answer some questions about your health concerns & symptoms
Treatment
Connect with a clinician 100% online, no appointment needed
Delivery
Get your medication delivered directly, if prescribed
Table of Contents
- Understanding Acetazolamide for Altitude Sickness
- Primary Uses of Acetazolamide
- How Acetazolamide Treats AMS
- Acetazolamide Treatment Timeline
- Acetazolamide in Pregnancy & Breastfeeding
- Acetazolamide vs. Diamox®: Pharmaceutical Specifications
- Acetazolamide Dosage Guidelines for Altitude Sickness
- Critical Safety Information
- Acetazolamide 250mg Tablet Composition
- Acetazolamide Side Effect Profile
- Absolute Contraindications
- Where Can I Buy Acetazolamide Online in the UK
- Acetazolamide FAQs
Understanding Acetazolamide for Altitude Sickness
Acetazolamide 250mg tablets (previously marketed as Diamox®) are available through Chemist Doctor's regulated online service following a medical consultation. This prescription medication helps prevent and manage acute mountain sickness (AMS) during high-altitude expeditions.
Primary Uses of Acetazolamide
While licensed for glaucoma and epilepsy management, Acetazolamide is prescribed off-label by UK clinicians for:
- Preventing AMS symptoms above 3,000m (9,842ft)
- Reducing headache, nausea and breathlessness during ascent
- Managing mild-moderate altitude sickness cases
As per NICE guidelines, off-label use requires explicit patient consent and clinical justification.
Off-Label Altitude Sickness Treatment
Acetazolamide's AMS application is considered off-label because:
- Original licensing focused on ocular conditions
- Dosage protocols differ from manufacturer recommendations
- Long-term altitude-specific safety data remains limited
Clinical studies in the British Medical Journal demonstrate 40-50% symptom reduction when used preventatively at altitude.
How Acetazolamide Treats AMS
This carbonic anhydrase inhibitor works through three key mechanisms:
- Stimulates bicarbonate excretion via kidneys
- Lowers blood pH to stimulate respiratory drive
- Reduces cerebrospinal fluid production
The combined effect improves oxygen saturation by 8-12% according to eMC data.
Acetazolamide Treatment Timeline
| Purpose | Start Time | Duration |
|---|---|---|
| Prevention | 24-48h pre-ascent | 2 days post-summit |
| Symptom Management | At first AMS signs | Until 48h symptom-free |
Medicated vs Natural Recovery
Clinical data shows:
- Untreated AMS: 24-48h recovery at stable altitude
- With Acetazolamide: 12-24h symptom resolution
Note: Immediate descent remains critical for severe cases regardless of medication use.
Acclimatization Remains Essential
While effective, Acetazolamide doesn't replace:
- Gradual ascent protocols (≤500m/day above 3,000m)
- Mandatory rest days every 3-4 days
- Immediate descent for worsening symptoms
The NHS advises combining medication with proper ascent planning.
Recognising Early Altitude Sickness Symptoms
The NHS categorises these warning signs requiring immediate ascent cessation:
- Persistent headache: Unresponsive to paracetamol & hydration
- Exertional fatigue: Disproportionate to activity level
- Vertigo: Lightheadedness worsening with movement
- Sleep architecture disruption: Cheyne-Stokes breathing patterns
🗒️ Clinician Note: Symptoms typically resolve within 24-48hr with 300-500m descent. Always carry pulse oximeters - SpO₂ below 85% requires emergency action.
Altitude Sickness Emergency Protocols
HAPE (High Altitude Pulmonary Edema)
Fluid accumulation in lung alveoli:
- Resting SpO₂ ≤75% (sea level baseline 95-100%)
- Productive cough with pink frothy sputum
- Chest rales audible without stethoscope
HACE (High Altitude Cerebral Edema)
Cerebral swelling indicators:
- Ataxic gait (cannot walk heel-to-toe)
- Glasgow Coma Scale ≤13
- Papilledema on fundoscopic exam
Immediate Response Protocol
- Descend ≥500m immediately (day/night)
- Administer dexamethasone 8mg IM/IV (HACE)
- Use portable hyperbaric chambers (Gamow bag)
- Supplemental O₂ ≥4L/min via non-rebreather
Source: NICE Emergency Guidelines
Acetazolamide in Pregnancy & Breastfeeding
UK Teratology Information Service (UKTIS) recommendations:
| Scenario | Recommendation | Risk Category |
|---|---|---|
| First Trimester | Contraindicated | Category C |
| Breastfeeding | Monitor infant for diuresis | Low excretion |
⚠️ Important: Fetal acid-base imbalance risks require strict consultant supervision.
Managing Altitude Sickness Without Medication
When Acetazolamide isn't available:
- Hydration: 3-4L/day + electrolyte monitoring
- Ascent Rate: ≤300m/day above 2,500m
- Nutrition: ≥4000kcal/day, 60% carbohydrates
- O₂ Supplementation: Nighttime nasal cannula 2L/min
Supported by British Mountaineering Council field studies.
Expedition Medical Kits: Order Acetazolamide + Oximeters with next-day tracked delivery.
Acetazolamide vs. Diamox®: Pharmaceutical Specifications
Acetazolamide (Diamox®) details:
- Generic Status: Available since 2012 (UK generic substitution policy)
- Manufacturer: Mercury Pharma Group Ltd
- Identification: White convex tablet marked FW147 (PL 07425/0036)
- Legal Classification: POM (Prescription Only Medicine)
Verified in eMC product data.
Acetazolamide Dosage Guidelines for Altitude Sickness
| Clinical Scenario | Dosing Regimen | Duration |
|---|---|---|
| Prophylaxis (≥3,000m ascent) | 125mg BD (½ tablet) | Start 48h pre-ascent → 48h post-summit |
| Mild AMS management | 250mg BD | Until 24h symptom-free + 48h post-resolution |
| Rapid ascent protocols | 250mg BD | During ascent + 72h at maximum altitude |
⚠️ Important: Always combine with acclimatization protocols per UK Climbing Medicine guidelines.
Critical Safety Information
Absolute Contraindications
- Sulfonamide allergy history
- Severe renal impairment (eGFR <30)
- Metabolic acidosis (pH <7.2)
Administration Cautions
- Conduct trial dose 3-4 days pre-expedition
- Monitor serum electrolytes daily
- Maintain fluid intake ≥2.5L/day
As per NICE CKS guidance.
Expedition-Ready Packs: Order Acetazolamide + Monitoring Kit with GPhC-registered pharmacist support.
Acetazolamide 250mg Tablet Composition
Active substance: Acetazolamide (250mg/tablet)
Excipient Profile (eMC approved)
- Lactose monohydrate (milk sugar derivative)
- Maize starch (corn starch)
- Bovine gelatin (E441)
- Glycerol (E422)
- Purified water
- Magnesium stearate (E470b)
⚠️ Contains lactose - unsuitable for galactosaemia patients
Acetazolamide Side Effect Profile
Common Reactions (≥1/100 patients)
- Polyuria (excessive urination)
- Paraesthesia (limb tingling)
- Transient myopia
Serious Reactions (MHRA Yellow Card Reportable)
| System | Reactions | Action Required |
|---|---|---|
| Renal | Haematuria, crystalluria | Stop treatment |
| Hepatic | Jaundice, dark urine | LFT monitoring |
Report via MHRA Yellow Card Scheme
Anaphylaxis Recognition
Signs requiring immediate 999 call:
- Angioedema (facial swelling)
- Stridor (high-pitched breathing)
- Hypotension (BP <90/60mmHg)
Absolute Contraindications
- Hypersensitivity: Sulphonamide allergy history
- Renal Impairment: eGFR <30ml/min/1.73m²
- Metabolic Disorders: Hyperchloraemic acidosis
🔍 Screening Essential: Verify renal function & allergy history via Online Doctor consultation prior to prescribing.
Where Can I Buy Acetazolamide Online in the UK
Secure Acetazolamide Prescription & Next-Day Delivery Service
Order Acetazolamide with confidence through our UK-registered travel health specialists, who review all requests within 4 working hours. We guarantee same-day prescription approval for eligible travellers and dispatch orders placed before 3pm for next-day tracked delivery.
Our Acetazolamide service combines competitive pricing with strict adherence to MHRA safety standards, ensuring your altitude sickness medication is dispensed through GPhC-registered pharmacies. Every purchase includes:
- Discreet packaging with ascent timing guide
- GDPR-compliant consultation
- 250mg tablets (UK-licensed Diamox formulation)
Our Acetazolamide clinical team ensures:
- Full ascent itinerary review (altitude gain rate and sleeping elevation)
- Sulfonamide allergy screening (critical contraindication check)
- Personalised dosing (typically 125-250mg twice daily starting 1-2 days before ascent)
Always consult your GP if you have kidney disease, liver cirrhosis, or metabolic acidosis. Not suitable during pregnancy. Must continue for 48 hours after reaching highest altitude.
Getting your medication is quick and easy with our simple 4-step process:
Start Consultation
Complete our brief health questionnaire about your medical history and current health.
Medical Review
UK-registered clinicians review your consultation for safe prescribing.
Pharmacy Processing
If approved, our partner pharmacy prepares your medication.
Fast Dispatch
Your order is dispatched via your chosen delivery method.
What does the online consultation involve?
You'll answer questions about your medical history and current health to ensure safe prescribing. Honest responses are vital for your safety.
How do I reorder medication?
Use the login details emailed after your first order to access your account and reorder.
How does the secure chat portal work?
Clinicians may contact you via your account's chat portal to discuss your treatment. Respond securely within your account.
At Chemist Doctor, we respect your privacy and ensure complete discretion at every step.
Discreet Packaging
All orders are sent in tamper-evident, plain white boxes sealed within anonymous grey mailing bags.
Secure Data
Your personal and medical information is kept strictly confidential with SSL encryption.
Private Consultations
All consultations are conducted privately by UK-registered clinicians.
Anonymous Billing
Credit card statements show a neutral descriptor with no reference to medications.
Will my GP be informed about my order?
Only with your consent. We recommend updating your GP directly for seamless care.
We offer two reliable delivery options to suit your needs:
| Service Type | Delivery Speed | Order Cut-off | Carrier |
|---|---|---|---|
| Standard Delivery | 2-3 business days | No cut-off | Royal Mail |
| Premium Next-Day Delivery | Next business day | 3 PM weekdays | Royal Mail 24 |
Next-day delivery guarantee applies to orders approved before 3 PM to these regions:
- England
- Scotland
- Wales
- Northern Ireland
Service Restrictions: We currently cannot deliver to: Republic of Ireland, Continental Europe, USA, or Canada
Is packaging discreet?
Yes. All orders are shipped in plain, unmarked packaging via tracked courier services.
Do I need to stay home for delivery?
No. You'll receive a tracking number to monitor your parcel's progress.
Do you deliver on weekends or bank holidays?
Deliveries occur Monday–Friday only. We do not ship on weekends or UK bank holidays.
What should I do if my order hasn't arrived?
Use your tracking number to locate the parcel or contact our support team for assistance.
Can I receive delivery updates via SMS?
Yes. Provide your mobile number at checkout for courier updates. We will not use it for marketing purposes.
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How long do refunds take to process?
Card payments: Refunds appear in 3–5 days.
Bank transfers: We'll contact you for account details to return funds.
Why was my order declined?
Declined orders are not charged. Card authorisations release funds within 3–5 days (contact your bank for details).
Can I return prescription medication?
No. UK law prohibits returns of dispensed prescription treatments for safety reasons.
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Acetazolamide FAQs
How does Acetazolamide differ from other altitude sickness medications?
Unlike steroids like dexamethasone, Acetazolamide addresses the root cause of AMS through carbonic anhydrase inhibition rather than symptom suppression. Clinical trials show 40% greater efficacy compared to NSAIDs (BMJ 2012;345:e6779).
Can I continue ascending if I'm taking Acetazolamide tablets?
No. The UK Mountain Medicine Council mandates cessation of ascent until 24 hours after complete symptom resolution. Acetazolamide aids acclimatization but doesn't eliminate AMS risk during continued climbing.
Does physical fitness reduce the need for Acetazolamide?
No. Hypoxia responses are independent of fitness levels. A 2020 Lancet study showed elite athletes have similar AMS susceptibility as recreational climbers (Lancet 2020;395:369-379).
What should I do if I develop side effects at high altitude?
Immediate actions:
- Discontinue medication
- Descend ≥500m if possible
- Contact our 24/7 medical team
How should I store Acetazolamide during expeditions?
Ideal storage conditions:
- Temperature: 15-25°C
- Humidity: <60% RH
- Protection: Moisture-proof container
Can I consume alcohol while taking Acetazolamide?
Contraindicated. Alcohol exacerbates diuretic effects, increasing dehydration risk by 70%. Maintain 3-4L daily fluid intake.
Is Acetazolamide safe during pregnancy?
Not recommended. Limited placental transfer studies. The Royal College of Obstetricians advises against high-altitude travel during pregnancy.
 | Authored by Nabeel M |
Medical Content Manager & Pharmacy Associate
Nabeel is a co-founder of Chemist Doctor. He works closely with our medical team to ensure the information is accurate and up-to-date.
 | Reviewed by Usman M (2073618) |
Director & Superintendent Pharmacist
Usman is a co-founder, and superintendent pharmacist of Chemist Doctor. He leads the clinical team and online prescribing services, utilising his expertise.
Review Date: 17 April 2025
Next Review: 7 November 2025
Published on: 17 April 2025
Last Updated: 18 April 2025
Responsible Pharmacist
 | Usman Mir Superintendent GPhc: 2073618 |
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Chemist Doctor is an online pharmacy and online doctor service, owned and operated by Chem Doc Ltd (Company Reg. 16478812). Prescriptions are managed by our sister company, Inspire Pharmacy (GPhC No. 9011381), a registered pharmacy located at Unit 18, Croft Road Industrial Estate, Newcastle-under-Lyme, Staffordshire, ST5 0TW. The content on this website is for informational purposes only. It should support, not replace, advice from your healthcare provider. Always consult your doctor if you suspect a health issue or before beginning new medication. Ensure you read the leaflets provided with any medicines. For further details, visit our policies and terms & conditions at the bottom of each page.
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