Heat exhaustion is a condition whose symptoms may include heavy sweating and a rapid pulse, a result of your body overheating. It’s one of three heat-related syndromes, with heat cramps being the mildest and heatstroke being the most severe.
Causes of heat exhaustion include exposure to high temperatures, particularly when combined with high humidity, and strenuous physical activity. Without prompt treatment, heat exhaustion can lead to heatstroke, a life-threatening condition. Fortunately, heat exhaustion is preventable.
SYMPTOMS
Signs and symptoms of heat exhaustion may develop suddenly or over time, especially with prolonged periods of exercise. Possible heat exhaustion signs and symptoms include:
- Cool, moist skin with goose bumps when in the heat
- Heavy sweating
- Faintness
- Dizziness
- Fatigue
- Weak, rapid pulse
- Low blood pressure upon standing
- Muscle cramps
- Nausea
- Headache
Other causes
Besides hot weather and strenuous activity, other causes of heat exhaustion include:
- Dehydration, which reduces your body’s ability to sweat and maintain a normal temperature
- Alcohol use, which can affect your body’s ability to regulate your temperature
- Overdressing, particularly in clothes that don’t allow sweat to evaporate easily
Risk factors
Anyone can develop heat exhaustion, but certain factors increase your sensitivity to heat. They include:
- Young age or old age. Infants and children younger than 4 and adults older than 65 are at higher risk of heat exhaustion. The body’s ability to regulate its temperature isn’t fully developed in the young and may be reduced by illness, medications or other factors in older adults.
- Certain drugs. Medications that affect your body’s ability to stay hydrated and respond appropriately to heat include some used to treat high blood pressure and heart problems (beta blockers, diuretics), reduce allergy symptoms (antihistamines), calm you (tranquilizers), or reduce psychiatric symptoms such as delusions (antipsychotics). Additionally, some illegal drugs, such as cocaine and amphetamines, can increase your core temperature.
- Obesity. Carrying excess weight can affect your body’s ability to regulate its temperature and cause your body to retain more heat.
- Sudden temperature changes. If you’re not used to the heat, you’re more susceptible to heat-related illnesses, such as heat exhaustion. Traveling to a warm climate from a cold one or living in an area that has experienced an early heat wave can put you at risk of a heat-related illness because your body hasn’t had a chance to get used to the higher temperatures.
- A high heat index. The heat index is a single temperature value that considers how both the outdoor temperature and humidity make you feel. When the humidity is high, your sweat can’t evaporate as easily and your body has more difficulty cooling itself, making you prone to heat exhaustion and heatstroke. When the heat index is 91 F (33 C) or higher, you should take precautions to keep cool.
Body fitness 