The ultraviolet rays of the sun can cause severe and very debilitating sunburn in lighter-skinned persons. Breathing and swallowing dust when traveling on unpaved roads or in arid areas may be followed by nausea and malaise, and may cause increased susceptibility to infections of the upper respiratory tract. Traveling in high altitudes may lead to insomnia, headache, nausea, and altitude sickness, even in young and healthy persons, and can cause distress to those with cardiac or pulmonary conditions. Individual susceptibility to acute mountain sickness is highly variable. Travelers who are at greatest risk are those who ascend rapidly to tourist sites in the Andes and Himalayas.
Medication is available to hasten the process of acclimatization to high altitudes.