A pre-trek check-up is only as good as the information you bring to it. Tell a doctor you are going on a walking holiday and you will get a cheerful nod. Tell them you will sleep at 5,160 m, eight days' walk from a road, where the only way out is a helicopter that flies in good weather — and you will get a very different, far more useful conversation.
Few doctors have specialist knowledge of altitude, and they do not need it. What they need from you is the facts of the trip. What you need from them is an honest assessment of whether any condition you have changes the plan, and the prescriptions to go with it. This guide helps you run that appointment.
This article is general information for trip planning, not medical advice.
Who Needs a Check-Up
A healthy adult under 50 with no medical conditions, heading for a moderate trek, does not strictly need a medical. A travel clinic visit for vaccines and prescriptions is still worthwhile. A proper check-up is strongly advisable if any of these apply:
- You are over 50, or over 40 with risk factors for heart disease — smoking, high blood pressure, high cholesterol, diabetes, or a strong family history.
- You have any long-term condition: heart or lung disease, asthma, diabetes, epilepsy, kidney disease, a blood disorder.
- You take regular prescription medication.
- You have had altitude sickness before, particularly fluid on the lungs (HAPE) or brain swelling (HACE).
- You are pregnant or planning to be.
- You have had surgery, a blood clot, or a serious illness in the last year.
- You will sleep above 4,500 m, cross a 5,000 m pass, or climb a trekking peak.
- Your route is remote, with no road or airstrip for many days.
- You have done very little exercise recently.
Go six to eight weeks before departure, so there is time for tests, vaccines and a trial of any new medication.
What to Tell Your Doctor
Bring the itinerary. These are the facts that matter, with the numbers for three common routes as an example.
| Fact | Poon Hill | Annapurna Base Camp | Everest Base Camp |
|---|---|---|---|
| Maximum altitude | 3,210 m | 4,130 m | 5,545 m at Kala Patthar |
| Highest sleeping altitude | About 2,870 m | 4,130 m | About 5,160 m |
| Nights above 3,000 m | None | About three | About nine |
| Walking per day | 4 to 6 hours | 5 to 7 hours | 5 to 7 hours |
| Days from a road | One | Two to three | Reached by mountain flight |
| Evacuation | Jeep track nearby | Helicopter | Helicopter |
| Night temperatures at the top | Around freezing | Down to about -10°C | Down to about -15°C or colder |
- The air: at 5,000 m there is roughly half the oxygen available at sea level.
- The exertion: sustained, moderate effort for many consecutive days, with a pack of 5 to 8 kg.
- The remoteness: basic lodges, no doctor, limited pharmacy, and evacuation that depends on weather.
- Everything you take: prescription drugs, over-the-counter medicines, supplements and contraception.
Questions to Ask
- Is there anything in my history that makes sleeping at this altitude inadvisable?
- Do any of my regular medicines behave differently at altitude, in the cold, or with dehydration?
- Should I take acetazolamide? If so, what dose, when do I start, and can I try it at home first?
- I have been told I may be allergic to sulfa drugs — does that rule acetazolamide out for me?
- Will you prescribe a stand-by antibiotic for severe diarrhoea, with written instructions on when to use it?
- Which painkillers are safe for me — in particular, can I take anti-inflammatories?
- What vaccines do I need, and is rabies vaccination sensible for this route?
- If my condition flares up on the trek, what should I do first, and at what point should I descend?
- Can you give me a letter listing my conditions and medicines by their generic names?
- Is there anything I should tell my insurer?
Write the answers down. The detail on altitude medication is in our guide to Diamox, and the general picture in the pre- and post-trek medication guide.
Tests Worth Considering
No test predicts who will get altitude sickness. Fit people get it; unfit people sometimes do not. What tests can do is reveal a problem that altitude would make worse.
| Check | Who should consider it | Why it matters on a trek |
|---|---|---|
| Blood pressure | Everyone over 40; anyone on treatment | Blood pressure often rises in the first days at altitude |
| Resting ECG, and an exercise test if advised | Over 50; cardiac risk factors; chest symptoms on exertion | Altitude and exertion both increase the heart's workload |
| Full blood count and iron stores | Women; vegetarians; anyone tired or pale | Anaemia and low iron reduce oxygen-carrying capacity and slow acclimatisation |
| Blood sugar and HbA1c | Diabetics; those at risk | Control needs to be stable before a long trek |
| Kidney function | Kidney disease; regular anti-inflammatory use; before acetazolamide if advised | Dehydration and some trek medicines stress the kidneys |
| Lung function | Asthma, chronic lung disease, long-term smokers | Establishes a baseline and checks control |
| Thyroid function | Known thyroid disease | Affects cold tolerance and energy |
| Pregnancy test | If there is any possibility | Changes advice on altitude, vaccines and medication |
If iron stores are low, six to eight weeks is enough time to start correcting them — one of the few things you can do before a trek that genuinely helps your body adapt.
Conditions That Need Extra Planning
Very few conditions rule out trekking altogether. Many change which trek you should choose and what you carry.
- Well-controlled asthma, diabetes and high blood pressure are all compatible with trekking, with preparation.
- Stable heart disease needs a cardiologist's opinion and usually a lower route.
- Previous HAPE or HACE makes a recurrence more likely; a slower ascent and preventive medication are normally advised.
- Pregnancy: most guidance advises against sleeping at high altitude, and remoteness from obstetric care is the bigger issue.
- Sickle cell disease, severe lung disease, unstable angina and recent blood clots are generally considered reasons not to go high.
Each of these is covered in trekking in Nepal with a medical condition. Choosing a route with a lower maximum altitude and quick road access — see trek difficulty grades — solves many problems before they start.
Teeth, Eyes and Feet: The Unglamorous Checks
Teeth
See a dentist a month or two before you go. A loose filling or a low-grade infection that is no trouble at home can flare into severe pain at altitude, and there is no dentistry on the trail — only painkillers and a long walk out. This is one of the commonest avoidable reasons for abandoning a trek.
Eyes
- Glasses: bring a spare pair and your prescription.
- Contact lenses: usable, but hygiene is difficult with cold water and dusty air. Bring daily disposables, hand sanitiser and glasses as a back-up. Do not sleep in lenses.
- Sunglasses: category 3 or 4 with side protection. Snow blindness is painful and entirely preventable.
- Previous eye surgery: mention it. Some older forms of corrective surgery cause vision changes at altitude.
Feet
- Deal with ingrown toenails, verrucas and fungal infections before you travel.
- Have your boots properly worn in — at least 50 km — before the trek, in the socks you will wear.
- If you use orthotics, bring them and a spare pair.
Foot care on the trail is in knee pain, blisters and painkillers.
Paperwork to Bring
- A doctor's letter listing conditions, medicines by generic name and dose, and allergies.
- Copies of prescriptions — needed for customs if you carry controlled medicines, and for replacing anything lost.
- Your insurance certificate and the 24-hour emergency number, with pre-existing conditions declared.
- Blood group, if you know it.
- An emergency contact at home.
- Photos of all of it on your phone, and a paper copy in your day pack.
Give your guide a copy of the medical letter on day one. In an emergency it is the first thing a doctor or a helicopter medic will ask for.
We Provide This Service: Pre- and Post-Trek Health Support
Green Compass Treks supports the medical side of your trip from booking to departure home. We are not doctors and we do not assess fitness to trek — but we make it easy for your doctor to do so, and we act on what they say.
- An altitude profile for your doctor: day-by-day sleeping altitudes, maximum height, daily walking hours and evacuation options for your exact itinerary.
- Your medical details handled in confidence: tell us about conditions, medication and allergies when you book, and they go only to the people planning your trek and to your guide.
- Route advice when a condition calls for a lower maximum altitude, extra acclimatisation days or quick road access — and an honest answer if we think a route is unwise.
- A pre-trek briefing in Kathmandu or Pokhara where your guide goes through your medication and what to do if a condition flares.
- On the trek: a first-aid-trained guide with a medical kit and, on high routes, a pulse oximeter and emergency oxygen.
- After the trek: help arranging a clinic appointment if you have any symptoms before flying home.
Send us your intended route and dates and we will reply with the profile to take to your appointment.
