Understanding Altitude Sickness in the Himalayas
Altitude sickness, or Acute Mountain Sickness (AMS), is the most common health risk on Nepal treks above 2,500m. It occurs when the body doesn't have time to adjust to decreasing oxygen levels at higher elevations. Understanding AMS is essential for every trekker — it doesn't discriminate based on age, fitness, or experience.
Symptoms of AMS
Early symptoms include headache, loss of appetite, nausea, fatigue, and difficulty sleeping. These are normal at altitude and usually resolve with proper acclimatization. Severe symptoms that require immediate descent include confusion, loss of coordination (ataxia), severe breathlessness at rest, and fluid in the lungs (HAPE) or brain (HACE).
The Golden Rules of Acclimatization
- Climb high, sleep low: Day hikes to higher elevations help your body adjust
- Don't ascend more than 500m sleeping altitude per day above 3,000m
- Take a rest day every 3-4 days of ascending
- Stay hydrated: Drink 3-4 liters of water daily at altitude
- Avoid alcohol and sleeping pills which mask symptoms
Diamox (Acetazolamide)
Diamox is a prescription medication that aids acclimatization. It works by increasing ventilation and urination, helping the body adjust faster. Consult your doctor before your trek — common side effects include tingling in fingers and increased urination. Start 125mg twice daily, 1-2 days before reaching 3,000m.
