Lack of Sweat

What is anhidrosis?
Anhidrosis is the absence of sweating in one or more parts of the body. Sweating releases heat from your body so you can cool down. If you cannot sweat your body will overheat, which can be dangerous and even life-threatening.

A severe case of anhidrosis, where most or all of the body does not sweat, may result in serious heat-related illnesses, including:

Cramps (painful and long-lasting muscle spasms in legs, arms, stomach area and back)
Heat exhaustion (signs are weakness, nausea, rapid heartbeat after strenuous activity in hot weather)
Heat stroke (extremely dangerous condition with body temperature at 104 degrees or higher; confusion; loss of consciousness; possibly coma and death)
It is not known how many people have anhidrosis. If only a small part of the body is affected, other parts of the body sweat to make up for the affected area. These cases are usually not dangerous because the body can still cool itself.

However, if you notice that you do not sweat at all or very little on hot days during activities that normally cause sweating, it is important to talk with your doctor.

What are the causes of anhidrosis?
If you have anhidrosis your sweat glands do not work properly. There are a number of possible causes. Some people were born with the condition, or developed it later in life because of problems with the nerves and skin.

Other causes of anhidrosis include:

Skin damage from burns, radiation therapy, or pore-clogging diseases such as psoriasis
Damage to the sweat glands from surgery, trauma or scar formation
Nerve damage caused by diabetes, alcoholism, and Guillain-Barre syndrome
Inherited disorder of the metabolic system (Fabry disease)
Drugs that can interfere with sweat gland function, such as botulism toxin type A, morphine, and antipsychotics
What are signs and symptoms of anhidrosis?
If you have anhidrosis, these signs and symptoms may appear during hot weather activity:

Little or no sweating
Dizziness
Flushing
Muscle cramps
Overall weakness
Feeling hot and not able to cool off
If you have these symptoms, get out of the heat immediately and into a shaded area or indoors, preferably with air-conditioning. Loosen your clothes and if possible apply cool damp cloths to your body. Seek medical attention if the symptoms don’t get better as you cool down. When you see your primary doctor, be sure to talk about your lack of sweating.