Medically significant overheating of the body, inducing heavy sweating and a rapid pulse, can give rise to one of three heat syndromes. The mildest of these is heat cramps, which is experienced as pain in the legs and abdomen. For a victim of heat cramps, remove excess clothing, and encourage them to drink fluids. Stretch and massage the painful areas. Do not provide salty food or drink, due to electrolyte imbalance in the blood.
In case of heat exhaustion (where the skin feels cool, moist, pale, ashen and flushed) or the most severe syndrome, heat stroke (loss of consciousness caused by overheating), the goal is to lower the victim’s temperature from around 40 degrees down to 38. Apply wet towels, especially to the back of the neck and under the arms. Fan the victim and spray water on their skin. Remove most of their clothing. Give them small amounts of cool water to drink and call for emergency medical response if the condition worsens.