Heatstroke is caused by prolonged exposure to high temperatures or by doing physical activity in hot weather. You are considered to have heatstroke when your body temperature reaches 104 F (40 C) or higher. High humidity, certain health problems and some medications increase your risk of heatstroke. So does being a young child or older adult.
Heatstroke is the progression of two worsening heat-related conditions. When your body overheats, you first may develop heat cramps. If you don't cool down, you may progress to symptoms of heat exhaustion, such as heavy sweating, nausea, lightheadedness and feeling faint.
Heatstroke occurs if your body temperature continues to rise. At this point, emergency treatment is needed. In a period of hours, untreated heatstroke can cause damage to your brain, heart, kidneys and muscles. These injuries get worse the longer treatment is delayed, increasing your risk of serious complications or death.
Heatstroke symptoms include:
Heatstroke follows two less serious heat-related conditions:
When to see a doctor
Take immediate action to cool the overheated person while waiting for emergency treatment.
Heatstroke can occur in these ways:
In either type of heatstroke, your condition can be brought on by:
Anyone can develop heatstroke, but several factors place you at increased risk:
A possible complication of heatstroke is shock, which is a condition caused by a sudden loss of blood flow. Signs of shock include a very low blood pressure, blue lips and nails, and cool, clammy skin.
If you or others don't act quickly on the symptoms of heatstroke, you could die or experience damage to your brain or other vital organs. In response to heatstroke, these organs swell, and if you don't cool your body temperature quickly, the damage from this swelling could be permanent.
Tests and diagnosis
It's usually apparent to doctors if you have heatstroke, but they may order laboratory tests to confirm their diagnosis and rule out other causes of your symptoms. These tests include:
Treatments and drugs
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:
Lifestyle and home remedies
Home treatment isn't sufficient treatment for heatstroke. If you have signs or symptoms of heatstroke, seek emergency medical help. Others should take steps to cool you off while waiting for emergency help to arrive.
If you notice signs of heat-related illness before any noticeable signs or symptoms of heatstroke appear, take action to lower your body temperature and prevent your condition from progressing to heatstroke. In a lesser heat emergency, such as heat cramps or heat exhaustion, the following steps may be sufficient to lower your body temperature:
Heatstroke is predictable and preventable. Take these steps to prevent heatstroke during hot weather:
Last Updated: 2011-09-02
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