Acute Mountain Sickness is the single biggest risk above 3,500 m — and it's almost entirely preventable. Here's how we manage it.
What actually happens at altitude
As you climb, the air thins and every breath carries less oxygen. Your body adapts — breathing faster, making more red blood cells — but that adaptation takes time. Push up too quickly and you risk Acute Mountain Sickness (AMS): headache, nausea, poor sleep and fatigue.
Left unchecked, AMS can progress to the serious, life-threatening forms — HACE (brain) and HAPE (lungs). The single most important thing to understand is that altitude illness is about the rate of ascent, not your fitness. Strong, young trekkers get it too.
The golden rules of acclimatisation
Climb high, sleep low. Above 3,000 m, we limit the gain in sleeping altitude to roughly 300–500 m per night and build in rest days. Hydrate hard, walk at a conversational pace, and never ignore a headache that won't shift.
Our itineraries are deliberately unhurried for exactly this reason — extra nights above 3,500 m aren't padding, they're safety. Diamox can help, but it's a supplement to good pacing, not a substitute.
Knowing when to descend
The rule is simple and absolute: if symptoms are worsening, you go down. A few hundred metres of descent often resolves AMS completely. Our guides are trained to spot the warning signs early and carry the means to respond.
Every trip runs with comprehensive medical cover and a clear evacuation plan. Respect the mountain's timeline and the high passes will reward you.
