Altitude sickness, or Acute Mountain Sickness (AMS), is the primary health risk on high-altitude treks in Nepal. Understanding it is essential for a safe journey.
What Causes It
As you ascend, air pressure decreases and oxygen levels drop. Your body needs time to adapt to reduced oxygen at high altitudes. AMS typically affects trekkers above 2,500m and can impact anyone regardless of fitness level.
Symptoms to Watch For
Mild AMS presents as headache, nausea, dizziness, fatigue, and loss of appetite. These are common and usually manageable. Severe AMS can progress to High Altitude Pulmonary Edema (HAPE) or High Altitude Cerebral Edema (HACE), both of which are life-threatening and require immediate descent and medical attention.
Prevention Strategies
The golden rule is to ascend gradually. Climb high, sleep low. Above 3,000m, your sleeping altitude should increase by no more than 300-500m per day. Include rest days every 3-4 days. Stay extremely well hydrated (3-4 liters per day). Avoid alcohol and sleeping pills. Eat well, even if appetite is reduced. Garlic soup, a trail favorite, is believed to help with acclimatization.
Medication
Acetazolamide (Diamox) is commonly used for prevention and treatment of mild AMS. Consult your doctor before your trek about whether it is appropriate for you. Our guides carry oximeters to monitor blood oxygen levels throughout the trek.
When to Descend
If symptoms worsen despite rest, or if any signs of HAPE or HACE appear (severe breathlessness at rest, confusion, loss of coordination), immediate descent is the only treatment. Our guides are trained to recognize these signs and will not hesitate to make descent decisions.
The good news: with a proper itinerary, experienced guides, and awareness, the vast majority of trekkers complete their journey without serious altitude issues.
