Altitude Sickness
Altitude Sickness occurs when ascending too quickly to high elevations, causing headaches and nausea. Preventive altitude medication is available through Chemist Doctor after online consultation with UK clinicians. Proper preparation can make mountain travel safer and more comfortable.
Find Altitude Sickness Treatments
Acetazolomide Tablets
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
What Causes Altitude Sickness?
Altitude sickness (acute mountain sickness) typically occurs when ascending above 2,500 metres (8,000 feet) too rapidly. At higher elevations, decreased atmospheric pressure reduces oxygen availability, triggering symptoms. Our bodies need time to adapt through proper acclimatisation, which should always be prioritised over medication.
Recognising Altitude Sickness Symptoms
Mild symptoms (appearing 6-24 hours after ascent):
- Persistent headache
- Nausea/vomiting
- Dizziness & fatigue
- Shortness of breath
- Sleep disturbances
Severe symptoms requiring immediate descent:
- Chest congestion with bubbly sounds
- Confusion/disorientation
- Loss of coordination
- Bluish skin discolouration
Source: NICE Clinical Guidelines
Altitude Sickness Treatment Options
Immediate first-line management:
- Stop ascent immediately
- Descend 500-1000 metres if symptoms persist
- Use supplemental oxygen if available
Medication Options
Acetazolamide (Diamox) - prescription medication that:
- Accelerates acclimatisation
- Reduces symptom duration by 50%
- Used for both prevention & treatment
Always consult a GP before high-altitude travel, especially if you have pre-existing conditions. Acetazolamide 250mg tablets are available following online consultation with our UK-registered prescribers.
Preventing Altitude Sickness
Golden rules for safe ascent:
| Altitude | Ascent Rate |
|---|---|
| Above 3,000m | Max 500m/day ascent |
| Every 1,000m gain | 2 rest days required |
Source: eMC Prescribing Information
Alternative Approaches to Manage Altitude Sickness
While Acetazolamide is the gold-standard treatment, these methods can support management:
- Controlled Ascent Protocol: Limit elevation gain to 300-500m daily above 2,500m
- Hydration Strategy: Maintain 3-4 litres daily (avoid overhydration)
- Dietary Adjustments: High-carbohydrate intake (70% of calories)
- Oxygen Supplementation: Portable systems for emergency use
Source: eMC Therapeutic Guidelines
Where Can I Buy Altitude Sickness Treatment Online in the UK
Secure Altitude Sickness Prescription & Next-Day Delivery Service
Order altitude sickness medication 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 altitude sickness service combines competitive pricing with strict adherence to MHRA safety standards, ensuring your medication is dispensed through GPhC-registered pharmacies. Every purchase includes:
- Discreet packaging with dosage guide
- GDPR-compliant consultation
- Acetazolamide 250mg tablets (PHE-recommended prophylaxis)
Our clinical team ensures:
- Full ascent profile review (including altitude gain rate)
- Screening for sulfa allergies (contraindication check)
- Personalised dosing schedule (start 1-2 days before ascent)
Always consult your GP if you have kidney/liver conditions or are pregnant. Not a substitute for proper acclimatisation. Seek immediate help for severe symptoms (HAPE/HACE).
Altitude Sickness FAQs
What exactly is altitude sickness?
Altitude sickness occurs when ascending too rapidly above 2,500m (8,000ft), reducing oxygen availability. Our online doctors classify it as:
Mild AMS: Headache + 1 symptom
Severe AMS: Neurological symptoms + respiratory distress
How quickly can symptoms develop?
Onset typically occurs 6-24 hours post-ascent. Severe cases (HACE/HAPE) may develop within 12 hours at extreme altitudes (>3,500m).
What worsens altitude sickness?
Key risk factors include:
- Ascending >500m/day above 2,500m
- Dehydration & alcohol consumption
- Pre-existing respiratory conditions
- Ignoring early symptoms
Can medication completely prevent AMS?
While Acetazolamide reduces risk by 50-70%, it's not a substitute for proper acclimatisation. Our medical team recommends:
Prevention Protocol:
125mg twice daily starting 1 day pre-ascent
Continue for 2 days post-maximum altitude
When is immediate descent crucial?
Descend immediately if experiencing:
- Altered mental state
- Ataxia (loss coordination)
- Productive cough with frothy sputum
- Oxygen saturation <85% (per pulse oximeter)
How does Acetazolamide work?
This carbonic anhydrase inhibitor:
1. Stimulates faster breathing
2. Reduces cerebrospinal fluid production
3. Lowers blood pH to enhance oxygen uptake
Effects begin within 2 hours, peaking at 8-12 hours.
Can I combine medication with natural methods?
Yes, our clinicians recommend:
Combined Approach:
- Acetazolamide 125mg BD
- 300m/day ascent limit
- Evening primrose oil (GLA supplementation)
- Hypoxic pre-conditioning exercises
Can I buy altitude sickness tablets without prescription?
Acetazolamide requires prescription in the UK. Our online doctor service provides safe access following medical assessment.
How quickly does Acetazolamide work?
When used preventatively, start 24-48 hours before ascent. Therapeutic effects begin within 2-4 hours.
 | 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 |
We Are Regulated
 |  |  |
 |  |  |
 |  |
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.
 |  |  |  |
Copyright 2025 Chemist Doctor. All Rights Reserved