Altitude Sickness

Altitude Sickness Treatment & Prevention | Travel Health | Allied Pharmacies

Altitude sickness, also known as acute mountain sickness (AMS), occurs when the body struggles to adjust to lower oxygen levels at high altitude. According to the NHS, it typically develops when travelling or climbing to heights above 2,500 metres above sea level too quickly.

The condition can affect anyone, regardless of age or fitness level, and can range from mild discomfort to a serious, life-threatening emergency. Planning ahead and seeking professional travel health advice before your trip is the best way to reduce the risk.

At Allied Pharmacies, our trained pharmacists provide travel health consultations, altitude sickness prevention advice and, where appropriate, prescription medication to help you travel safely. No GP referral is needed.

Use the postcode search below to find your nearest Allied Pharmacy offering travel health consultations.

What Is Altitude Sickness?

Altitude sickness happens when your body cannot get enough oxygen from the thinner air at high altitude. The higher you go, the lower the air pressure and the less oxygen is available with each breath. If you ascend too quickly without giving your body time to acclimatise, you may develop symptoms.

There are three main forms of altitude sickness:

• Acute Mountain Sickness (AMS) — the most common and mildest form, causing headache, nausea and fatigue
• High Altitude Pulmonary Oedema (HAPE) — a dangerous build-up of fluid in the lungs that causes severe breathlessness
• High Altitude Cerebral Oedema (HACE) — a life-threatening swelling of the brain that causes confusion, loss of coordination and can be fatal if not treated urgently

The NHS advises that altitude sickness cannot occur in the UK. It most commonly affects travellers visiting high-altitude destinations such as the Himalayas, Mount Kilimanjaro, the Andes, the Alps and cities like La Paz in Bolivia or Cusco in Peru.

Symptoms of Altitude Sickness

The NHS states that symptoms of altitude sickness typically appear 6 to 10 hours after reaching high altitude. Common symptoms include:

• Headache
• Nausea or vomiting
• Dizziness or light-headedness
• Loss of appetite
• Fatigue and exhaustion
• Difficulty sleeping
• Shortness of breath during physical activity

In most cases, mild symptoms will improve within 1 to 3 days if you stop ascending and allow your body time to adjust. However, if symptoms worsen or you develop signs of HAPE or HACE, you should descend immediately and seek emergency medical help.

When to Seek Urgent Medical Help

The NHS advises seeking immediate medical attention if you experience any of the following at high altitude:

• Severe breathlessness, even when resting
• A persistent cough, especially if producing frothy or blood-tinged sputum
• Confusion, disorientation or hallucinations
• Loss of balance or coordination (difficulty walking in a straight line)
• Extreme drowsiness or difficulty staying awake
• Blue or grey tinge to the lips or fingertips (cyanosis)

These symptoms may indicate HAPE or HACE, both of which are medical emergencies. You must descend to a lower altitude as quickly as possible and call for emergency help.

How to Prevent Altitude Sickness

The best way to prevent altitude sickness is to ascend gradually and give your body time to acclimatise. The NHS recommends the following precautions:

• Avoid travelling directly from low altitude to above 3,500 metres in a single day
• If possible, spend a few days acclimatising at an altitude below 2,500 metres before going higher
• Above 3,000 metres, do not increase your sleeping altitude by more than 300 to 500 metres per day
• Plan rest days every 3 to 4 days at higher altitudes, especially above 3,000 metres
• Stay well hydrated by drinking plenty of water
• Avoid alcohol during the first few days at altitude
• Avoid strenuous physical activity on your first day at a new altitude
• Eat a light, high-carbohydrate diet to help maintain energy

Altitude Sickness Medication: Acetazolamide (Diamox)

For travellers at higher risk or those visiting very high-altitude destinations, a preventative medication called acetazolamide (commonly known by the brand name Diamox) may be recommended. Acetazolamide helps your body adjust to altitude more quickly by increasing the rate of breathing and improving oxygen intake.

Key points about acetazolamide:

• It is a prescription-only medication that must be prescribed by a qualified healthcare professional
• Treatment usually starts 1 to 2 days before ascending to high altitude and continues during the ascent
• Common side effects include tingling in the fingers and toes, increased urination and a change in the taste of fizzy drinks
• It is not suitable for everyone — your pharmacist will check whether it is appropriate for you during your consultation

At Allied Pharmacies, our independent prescribing pharmacists can assess your suitability for acetazolamide and issue a prescription during your travel health consultation, saving you a separate GP appointment.

Popular High-Altitude Destinations

If you are planning a trip to any of the following destinations, you should consider a travel health consultation before you go:

• Mount Kilimanjaro, Tanzania — summit at 5,895 metres
• Everest Base Camp Trek, Nepal — reaching 5,364 metres
• Machu Picchu and Cusco, Peru — approximately 3,400 metres
• La Paz, Bolivia — approximately 3,640 metres
• The Alps (Mont Blanc) — summit at 4,808 metres
• Atlas Mountains, Morocco — peaks above 4,000 metres
• Lhasa, Tibet — approximately 3,650 metres

Even moderate-altitude destinations can cause symptoms in some people. If you are unsure whether your trip involves altitude risk, our pharmacists can advise you.

How the Altitude Sickness Service Works at Allied Pharmacies

Getting travel health advice at Allied Pharmacies is simple, convenient and does not require a GP referral.

• Travel consultation — your pharmacist will discuss your destination, itinerary, altitude exposure and medical history
• Prevention advice — you will receive personalised guidance on acclimatisation, hydration, pacing and travel safety
• Medication (if appropriate) — if your pharmacist recommends preventative medication such as acetazolamide, it can be prescribed and dispensed during the same appointment
• Travel health pack — you will leave with clear written advice to take with you on your trip

Why Choose Allied Pharmacies for Travel Health?

Allied Pharmacies makes it easy to prepare for high-altitude travel with expert pharmacy advice on your doorstep.

• No GP referral required — book directly with your local pharmacy
• Independent prescribing pharmacists who can issue prescriptions on the spot
• Convenient high street locations near you
• Fast appointments, often available within days
• Comprehensive travel health consultations covering altitude sickness, vaccinations and antimalarials

Related Travel Health Services

If you are preparing for a trip, you may also need other travel health services available at Allied Pharmacies:

• Antimalarials — prescription antimalarial tablets for travel to malaria-risk countries
• Cholera Vaccine — oral vaccine recommended for travel to areas with poor sanitation
• Hepatitis A Vaccine — recommended for many travel destinations worldwide
• Hepatitis B Vaccine — important for travellers to certain regions
• Japanese Encephalitis Vaccine — recommended for travel to parts of Asia and the Pacific
• Diphtheria, Tetanus and Polio Vaccine — booster recommended before many international trips
• Jet Lag Treatment — advice and medication to help manage jet lag on long-haul flights

Visit our full list of pharmacy services to see everything available at your nearest Allied Pharmacy.

Find Altitude Sickness Advice Near You

Travel health consultations for altitude sickness are available at participating Allied Pharmacies across the UK. Use the postcode search above to find your nearest pharmacy, check availability and book your appointment today.

Whether you are trekking to Everest Base Camp, climbing Kilimanjaro or visiting a high-altitude city, our pharmacists are here to help you prepare safely and enjoy your trip with confidence.

For more information about altitude sickness, visit the NHS altitude sickness page.