Hyperthermia

A pathological elevation of core body temperature above the normal set point (>37.5-38.3°C or >99.5-100.9°F), due to failure of thermoregulatory mechanisms where the body absorbs or produces more heat than it can dissipate. Not a change in temperature mediated by hypothalamic reset as in fever. Possible causes are exposure to high temperature and humidity, strenuous activitiy, dehydration with hypohidrosis, heavy/tight clothing, or drug/anesthetic reactions.