Altitude Sickness: What to Know Before Travelling to High-Altitude Destinations

The Health Risk of Going Too High, Too Fast

Altitude sickness (acute mountain sickness, AMS) occurs when the body ascends to high altitude faster than it can adapt to the reduced oxygen availability. It's relevant for Nigerians travelling to the Jos Plateau (1,200–1,829m), international mountain destinations, or high-altitude cities like Addis Ababa (2,355m), Quito (2,850m), or La Paz (3,650m).

Symptoms

• Mild AMS: headache (the defining symptom), fatigue, dizziness, nausea, poor sleep. Typically develops within 6–12 hours of arrival at altitude
• High altitude pulmonary oedema (HAPE): fluid accumulation in the lungs — breathlessness at rest, productive cough, cyanosis. Medical emergency
• High altitude cerebral oedema (HACE): brain swelling — severe headache, ataxia (stumbling), confusion, loss of consciousness. Life-threatening; descend immediately

Prevention Strategies

• Ascend gradually — don't gain more than 300–500m of sleeping altitude per day above 3,000m
• Stay well hydrated
• Acetazolamide (Diamox) — prescription medication that accelerates acclimatisation; discuss with a doctor before travel
• Avoid alcohol and sleeping tablets on arrival

FXMed's travel health consultations via our Elite Service can provide pre-travel fitness assessment, altitude medication prescription, and personalised travel health planning.