Before embarking on this once in a lifetime trip, be sure that you take the proper precautions necessary. If you plan to do the trail, be prepared as the route can be quite strenuous. Because the altitude is quite high, many officials recommend spending at least 2 days in Cusco to acclimate yourself to the decreased oxygen levels.
It is not uncommon for visitors to have problems with the altitude levels and, even more commonly, diarrhea. About 30%-50% of tourist experience diarrhea in the span of a typical two week trip. To reduce the likelihood of this happening, drink bottled water and avoid uncooked food.
Altitude: Machu Picchu and the Inca Trail are a breath-catching 300-700 meters (980-2,300 feet) lower than Cusco. But to be on the safe side about altitude effects, locally known as soroche; get an ample intake of fluids, but eliminate or minimize alcohol and caffeine consumption. (Both can cause dehydration, already a problem at high altitudes.) Smoking aggravates the problem. Some large hotels have an oxygen supply for their guests' use. The prescription drug acetazolamide can help offset the alkalosis caused by low oxygen at high elevations also see Machu Picchu Hiking Tours.