Heatstroke is a serious and potentially life-threatening condition that occurs when the body's temperature regulation system is overwhelmed by prolonged exposure to high temperatures and/or high humidity. It is a type of heat-related illness that can range in severity from mild to severe.

Symptoms of heatstroke can include a body temperature of 104 degrees Fahrenheit or higher, hot and dry skin, a rapid pulse, headache, dizziness, confusion, seizures, and loss of consciousness.

If you suspect someone is experiencing heatstroke, it is important to call for emergency medical assistance immediately. While waiting for medical help to arrive, move the person to a cooler location, remove any excess clothing, and attempt to cool their body temperature by any means available, such as applying cool water or ice packs to their skin or fanning them.

To prevent heatstroke, it is important to avoid prolonged exposure to high temperatures and humidity, especially during the hottest parts of the day. Wear lightweight and light-colored clothing, use fans or air conditioning to stay cool, and drink plenty of water and other fluids to stay hydrated.

Certain populations, such as young children, the elderly, and those with certain medical conditions, may be at higher risk of developing heatstroke and should take extra precautions in hot weather. It is important to stay aware of your body and any symptoms of heat-related illness, and seek medical attention if you experience any concerning symptoms.

Heatstroke can occur as a result of:

• Exposure to a hot environment. In a type of heatstroke, called nonexertional (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 illness.
• 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

Heatstroke is predictable and preventable. Take these steps to prevent heatstroke during hot weather:

• Wear loosefitting, lightweight clothing. Wearing excess clothing or clothing that fits tightly won't allow your body to cool properly.
• Protect against sunburn. Sunburn affects your body's ability to cool itself, so protect yourself outdoors with a wide-brimmed hat and sunglasses and use a broad-spectrum sunscreen with an SPF of at least 15. Apply sunscreen generously, and reapply every two hours — or more often if you're swimming or sweating.
• Drink plenty of fluids. Staying hydrated will help your body sweat and maintain a normal body temperature.
• Take extra precautions with certain medications. Be on the lookout for heat-related problems if you take medications that can affect your body's ability to stay hydrated and dissipate heat.
• Never leave anyone in a parked car. This is a common cause of heat-related deaths in children. When parked in the sun, the temperature in your car can rise 20 degrees F (more than 11 C) in 10 minutes.
• It's not safe to leave a person in a parked car in warm or hot weather, even if the windows are cracked or the car is in shade. When your car is parked, keep it locked to prevent a child from getting inside.
• Take it easy during the hottest parts of the day. If you can't avoid strenuous activity in hot weather, drink fluids and rest frequently in a cool spot. Try to schedule exercise or physical labor for cooler parts of the day, such as early morning or evening.
• Get acclimated. Limit time spent working or exercising in heat until you're conditioned to it. People who are not used to hot weather are especially susceptible to heat-related illness. It can take several weeks for your body to adjust to hot weather.
• Be cautious if you're at increased risk. If you take medications or have a condition that increases your risk of heat-related problems, avoid the heat and act quickly if you notice symptoms of overheating. If you participate in a strenuous sporting event or activity in hot weather, make sure there are medical services available in case of a heat emergency.

Heatstroke treatment centers on cooling your body to a normal temperature to prevent or reduce damage to your brain and vital organs. To do this, your doctor may take these steps:

• Immerse you in cold water. A bath of cold or ice water has been proved to be the most effective way of quickly lowering your core body temperature. The quicker you can receive cold water immersion, the less risk of death and organ damage.
• Use evaporation cooling techniques. If cold water immersion is unavailable, health care workers may try to lower your body temperature using an evaporation method. Cool water is misted on your body while warm air is fanned over you, causing the water to evaporate and cool your skin.
• Pack you with ice and cooling blankets. Another method is to wrap you in a special cooling blanket and apply ice packs to your groin, neck, back and armpits to lower your temperature.
• Give you medications to stop your shivering. If treatments to lower your body temperature make you shiver, your doctor may give you a muscle relaxant, such as a benzodiazepine. Shivering increases your body temperature, making treatment less effective.