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"I overheat often, but do not sweat. Why?"

ZocdocAnswersI overheat often, but do not sweat. Why?


22 yr old, active female. I have always had overheating problems, but I never sweat. It eventually leads to fainting because I can not cool down. I have had this issue since I was a kid. Is this something to actually be worried about? I drink plenty of liquids and I do not really eat unhealthy. I am mostly worried about this because I was on the back of a motorcycle and I almost fainted from over heating while the other person driving wasn't having heat problems.


The genetics of sweating are very complicated. Some people sweat more than others, and some people seem not to sweat at all. Absolute absence of sweating, however, is very uncommon, and is known as anhydrosis. Usually, anhydrosis occurs in combination with other symptoms of nerve dysfunction as part of a more complex autonomic neuropathy. Therefore, if you are otherwise completely healthy, it is unlikely that you have a true absence of sweating. Nevertheless, some people are more susceptible to the effects of heat, and they are more likely to suffer from heat stroke or from dehydration. Generally speaking, this can be countered by using good common sense, making sure to drink lots of fluid, and trying to stay out of direct sunlight or other very hot environments whenever possible. It would also be a great idea to have a full physical check up with your primary care doctor, if you have not done so in a while. The physical examination is a great opportunity to have your doctor check you out from head to toe and make sure there is not any underlying medical problem that might need treatment. Make an appointment to see your doctor at your earliest convenience.

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