Heatstroke is a condition caused by your body overheating, usually as a result of prolonged exposure to or physical exertion in high temperatures. This most serious form of heat injury, heatstroke, can occur if your body temperature rises to 104 F (40 C) or higher. The condition is most common in the summer months. Heatstroke requires emergency treatment. Untreated heatstroke can quickly damage your brain, heart, kidneys, and muscles. The damage worsens the longer treatment is delayed, increasing your risk of serious complications or death. Heatstroke signs and symptoms include: ● High body temperature. A core body temperature of 104 F (40 C) or higher, obtained with a rectal thermometer, is the main sign of heatstroke. ● Altered mental state or behavior. Confusion, agitation, slurred speech, irritability, delirium, seizures, and coma can all result from heatstroke. ● Alteration in sweating. In heatstroke brought on by hot weather, your skin will feel hot and dry to the touch. However, in heatstroke brought on by strenuous exercise, your skin may feel dry or slightly moist. ● Nausea and vomiting. You may feel sick to your stomach or vomit. ● Flushed skin. Your skin may turn red as your body temperature increases. ● Rapid breathing. Your breathing may become rapid and shallow. ● Racing heart rate. Your pulse may significantly increase because heat stress tremendously burdens your heart to help cool your body. ● Headache. Your head may throb Causes Heatstroke can occur as a result of: ● Exposure to a hot environment. In a type of heatstroke, called non-exertional (classic) heatstroke, being in a hot environment leads to a rise in core body temperature. This type of heatstroke typically occurs after exposure to hot, humid weather, especially for prolonged periods. It occurs most often in older adults and in people with chronic illnesses. ● Strenuous activity. Exertional heatstroke is caused by an increase in core body temperature brought on by intense physical activity in hot weather. Anyone exercising or working in hot weather can get exertional heatstroke, but it's most likely to occur if you're not used to high temperatures. In either type of heatstroke, your condition can be brought on by: ● Wearing excess clothing that prevents sweat from evaporating easily and cooling your body ● Drinking alcohol, which can affect your body's ability to regulate your temperature ● Becoming dehydrated by not drinking enough water to replenish fluids lost through sweating