Altitude Health: What Travelers Need to Know

Heading to high altitude? Mountains, ski trips, and highland towns are great, but lower oxygen changes how your body and your medicines work. This guide gives straightforward, useful tips you can use before and during your trip.

What altitude does to your body

When you go higher, the air has less oxygen. That can cause headache, dizziness, poor sleep, shortness of breath and fatigue — signs of acute mountain sickness (AMS). Symptoms can show up within hours and usually start between 6 and 24 hours after you arrive.

Serious problems — high altitude cerebral edema (HACE) or high altitude pulmonary edema (HAPE) — are rare but need immediate medical care. If someone gets very confused, can’t walk straight, or has severe breathlessness, get emergency help right away.

How altitude affects medications

Altitude can change how fast your body absorbs and clears drugs, and symptoms like vomiting or diarrhea make dosing less reliable. A few practical points:

- Acetazolamide (Diamox) is commonly used to prevent AMS. Doctors usually start it a day before ascent. It can make your urine more acidic and may interact with some diuretics or sulfa drugs. Tell your provider if you have kidney disease.

- Dexamethasone can treat or prevent severe AMS symptoms short term, but it’s not a substitute for proper descent if someone is sick.

- Pain relievers: ibuprofen or paracetamol help altitude headaches. Avoid heavy use of sedatives or strong sleep meds, which can worsen breathing at night.

- Chronic meds: people with heart, lung, or insulin-dependent diabetes should check dosing. Less oxygen may raise heart strain and change blood sugar patterns. Bring a recent prescription list and ask your doctor about dose tweaks before travel.

- Oxygen and inhalers: if you use inhalers, bring extra. Portable oxygen may be needed for severe lung disease; discuss this with your provider well before travel.

Practical travel checklist

- Ascend slowly: spend a night or two around 2,500–3,000 m before going higher when possible. Aim to increase sleeping elevation by no more than 300–500 m per day above 3,000 m.

- Pack smart: copies of prescriptions, an extra supply of meds in original labels, a small first-aid kit, and a pulse oximeter if you want to monitor oxygen saturation.

- Stay hydrated and eat light, regular meals. Avoid heavy alcohol and excessive heavy exercise during the first 24–48 hours at altitude.

- Know warning signs and have a descent plan. If symptoms worsen despite rest and simple meds, descend 500–1000 m and get medical attention.

If you have a chronic condition or take important medications, talk to your clinician before travel. A quick check can prevent big problems and keep your trip enjoyable.