Heat-Related Illnesses - Topic Overview
environmental and physical conditions can make it
hard to stay cool. Heat-related illness is often caused or made worse by
dehydration and fatigue.
Exercising during hot weather, working outdoors, and
overdressing for the environment increase your risk.
Drinking alcohol also increases your risk of dehydration.
medicines increase your risk of a heat-related
illness. Some medicines decrease the amount of blood pumped by the heart
(cardiac output) and limit blood flow to the skin, so your body is less able to
cool itself by sweating. Other medicines can alter your sense of thirst or
increase your body's production of heat. If you take medicines regularly, ask
your doctor for advice about hot-weather activity and your risk of getting a
Other things that may increase your risk of
a heat-related illness include:
- Age. Babies do not lose heat quickly and they do
not sweat effectively. Older adults do not sweat easily and usually have other
health conditions that affect their ability to lose heat.
- Obesity. People who are overweight have decreased
blood flow to the skin, hold heat in because of the insulating layer of fat
tissue, and have a greater body mass to cool.
- Heat waves. People who live in cities are especially vulnerable to illness
during a heat wave because heat is trapped by tall buildings and air
pollutants, especially if there is a high level of
- Chronic diseases, such as
heart failure, and cancer. These conditions change the
way the body gets rid of heat.
- Travel to wilderness areas or
foreign countries with high outdoor temperatures and humidity. When you go to a
different climate, your body must get used to the differences (acclimate) to keep your body temperature in a normal
Most heat-related illnesses can be prevented by keeping the
body cool and by avoiding dehydration in hot environments. Home treatment is
usually all that is needed to treat mild heat-related illnesses. Heat
exhaustion and heatstroke need immediate medical treatment.
Check your symptoms to decide if and when you should see a