Altitude illness can be prevented by acclimatization; that is, by a graduate rate of ascent (not more than 400 – 500 meters), allowing sufficient rest at various intermediate altitudes. The dry air of the mountains tends to dehydrate you so an increased fluid intake is necessary. Try to drink at least four liters of water a day. On the trail you can drink hot garlic soup that will help you to some extent. When we reach to our destination it is better to make some hiking up to a bit higher point and come down to the camp or hotel. This is a really good way to get acclimatization. You may take a Diamox 250mg tablets the night before flying / going to altitude. After the symptoms will often disappear and the trek can be resumed.
If you feel obviously suffering from the serious symptoms of AMS then descent should not be delayed even if it means going down in dark. In such case, should an emergency situation arise, horse, or porter will be arranged; or I myself carry you and run to lower (descend) altitudes. There are 3 radios in Namche Bazaar, Doctors at Khunde hospital in the Everest Area and HRA Clinics and in some trekking areas also has the Gamow Bag. The hospital or the clinic will take fees or charges for such services. I can arrange for immediate evacuation, by horse or helicopter, depending on the severity of the case.