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How Hyperthermia Works

Hyperthermia Causes
Strenuous activity in warm, humid air can overwhelm your body and lead to heat exhaustion.
Strenuous activity in warm, humid air can overwhelm your body and lead to heat exhaustion.

As we mentioned earlier, hyperthermia is what happens when your body is unable to control your internal temperature. Generally, this happens when you're overwhelmed with heat. One of the ways our bodies deal with excess heat is to generate sweat. The sweat absorbs heat from the skin and evaporates, pulling heat away from us. It's like a natural heat sink.

If you're dehydrated or in an environment that's too warm for your body to handle, you could suffer hyperthermia. Your body's temperature rises -- not because the hypothalamus is adjusting the internal thermostat, but because you're overwhelmed. It's one of the many symptoms of heat exhaustion and heat stroke.

If you're suffering from heat exhaustion, you may feel weak and dizzy. Your body will produce lots of sweat in an attempt to cool you down, which can lead to dehydration. You'll also lose a lot of salt as you sweat. Muscle cramps, dizziness, nausea, vomiting and headaches are other common symptoms. Unchecked, heat exhaustion can lead to heat stroke.

Heat stroke is a serious, potentially deadly condition. Symptoms include dizziness, disorientation, heat cramps and heat rash. With heat stroke, your body stops producing sweat. Your skin will feel hot to the touch and will be either moist or dry. Nausea is another common symptom of heat stroke. Heat stroke victims may also experience seizures.

While hyperthermia is just one symptom of heat exhaustion and heat stroke, it's an early indicator that something is wrong. If you feel uncomfortably warm, you may want to take a break and find a cool spot for a rest.

Other factors that can increase the risk of hyperthermia include circulation problems, lung and heart diseases, and diseased or damaged sweat glands. If you're on medication that affects your ability to sweat, you may also experience hyperthermia more readily.

Some drugs can also cause you to become overheated. It's important to discuss drugs and side effects with your doctor so that you can avoid dangerous conditions that could cause you to suffer hyperthermia.

Next, we'll look at ways to treat hyperthermia.