Heat Illness: Heat Stroke, Heat Exhaustion, Cramps and Rash

The body normally cools itself by sweating. In hot weather — especially when it is very humid — sweating alone may not be enough. Body temperature can then rise to dangerous levels and cause a heat illness.

What causes it, and who is at risk

Most heat illnesses happen when people stay out in the heat too long. Exercising or working outdoors in high heat can also bring one on.

Those most at risk are:

• older adults;
• young children;
• people who are sick or overweight.

Taking certain medicines, or drinking alcohol, also raises the risk.

The main heat illnesses

Heat stroke is life-threatening. Body temperature may rise above 106 °F (41 °C) within minutes. Signs include:

• dry skin;
• a rapid, strong pulse;
• dizziness;
• nausea;
• confusion.

If you see any of these signs, get medical help right away.

Heat exhaustion can develop after several days of high temperatures without enough fluids. Signs include:

• heavy sweating;
• rapid breathing;
• a fast, weak pulse.

Untreated, it can turn into heat stroke.

Heat cramps are muscle pains or spasms during heavy exercise, usually in the abdomen, arms or legs.

Heat rash is skin irritation from too much sweating. It is more common in young children.

Lowering the risk

• Drink fluids to prevent dehydration.
• Replace the salt and minerals you lose.
• Limit your time in the heat.

Sources

• MedlinePlus, U.S. National Library of Medicine, "Heat Illness," drawing on the Centers for Disease Control and Prevention. https://medlineplus.gov/heatillness.html
• Rewritten in hubnx's own words.