Hypothermia

Subnormal core body temperature (<35°C or <95°F), resulting from heat loss exceeding heat production and leading to progressive depression of cardiovascular, respiratory, and central nervous system function. Possible causes are enviromental exposure (weather, swimming), hypothyroidism, poor blood circulation, malnutrition, physical fatigue, drugs (alcohol, sedatives, antidepressants, antipsychotics, and β-blockers).