Fainting due to Heat Underlying Cause
Heat syncope is caused by exposure to a hot environment, usually for a prolonged period. The body cools itself by increasing blood flow to the skin, where heat is released into the environment. This shift of blood flow reduces the amount of blood flowing to other parts of the body, including the brain. If the blood flow to the brain is reduced too much, the brain stops functioning, which results in fainting. Heat syncope is more common in those who are dehydrated.
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