What are the dangers and consequences of high-altitude treks?

Trekking at high altitudes is dangerous. There are certain recommended responses to dangerous circumstances following the risk involved.
Risk: Before embarking on a high altitude hike, you should be informed of the effects of high altitudes on your health. Mountain sickness, headaches, nausea, and other forms of discomfort should be avoided.
Response: If you have any of these symptoms, notify the trip leader and always take medications in an emergency. Every camp has a stretcher, first-aid kit, and oxygen cylinders in an emergency