[Travelers exposed to extreme temperatures].

Sudden introduction of the unadapted human into extreme environments can result in serious, sometimes fatal, reactions. Most complications are due either to failure of thermoregulatory system or consecutive to the physiological responses to those environmental conditions. In addition to a number of minor diseases, cold can cause two major accidents, i.e., hypothermia and frostbite which can be enhanced at altitude. Moreover, the main disease in altitude conditions is represented by the acute mountain sickness which can lead to acute pulmonary and cerebral edema. Heat can cause heatstroke, dehydration, syncope, and other minor disorders. Prevention of these manifestations during stays in inhospitable climatic conditions for which the body is not suited requires knowledge of the environment and its dangers. Implementation of suitable measures can greatly reduces the incidence of adverse effects.