Trekkers are warned that altitude sickness can be a serious problem at the altitudes hiked to in Bhutan. If you feel sick, dizzy or have a worsening headache, stop and drink as much water as possible. If the symptoms persist, go back down the mountain.
 
Bhutanese guides are trained to look out for altitude sickness and other ailments that can affect trekkers. They are expert walkers who have been trained as trekking guides and follow routes that have been walked for centuries. All trekkers are required to strictly follow trekking rules to protect the fragile environment at high altitudes.