What is hyperhidrosis?

Sweating is a normal body function that helps control temperature. Sweat evaporates from the skin and cools the body. Heat and emotion will make most people sweat. Hyperhidrosis is too much sweating. It is more than what is needed to control body temperature.

Hyperhidrosis is a common skin problem. Five percent (5%) or more of all people may suffer from it. Hyperhidrosis can affect people of any age, however it usually starts before the age of 25.


In most children, we do not know exactly what causes hyperhidrosis. We do know that the sweat glands and nerves play a major role. Nerves send signals to the sweat glands that cause them to make sweat. Excessive sweating without a known cause is primary focal hyperhidrosis. Primary focal hyperhidrosis is the most common type of hyperhidrosis. It may run in families. In some children, a medical condition or medicine causes hyperhidrosis. This is called secondary hyperhidrosis.


Primary focal hyperhidrosis usually affects the hands, feet, and/or armpits. The signs and symptoms vary depending on which body parts are affected.

  • Armpit sweating may lead to visible marks on clothing. Your child may only want to wear dark clothing or hoodies to conceal these marks. They may be reluctant to raise their hand in class or give big hugs for fear that someone will see the wet marks.
  • Hand sweating may lead to problems at school (papers sticking or trouble writing with a pen or pencil), computers, touch-screen devices, sports, or other hobbies, such as playing a musical instrument. Teens and older children may be embarrassed to shake hands or hold hands with others.
  • Feet sweating may lead to odor and skin rash, or difficulty wearing certain types of shoes.

For some children, hyperhidrosis also affects emotions and confidence. Parents should check in with their child and encourage them to talk openly about how hyperhidrosis is affecting them.


A dermatologist diagnoses hyperhidrosis by talking with you and your child and doing a skin examination. Your doctor will ask questions about your child’s symptoms. Blood tests are not needed in most patients.


No single treatment works for everyone. Factors such as age, location, and severity may guide treatment decisions. Your doctor will help choose which treatments are best for your child. Discuss risks and benefits of treatments with your doctor.

  • Aluminum salts:
    Aluminum salts are medicines used directly on the skin. They plug sweat ducts and reduce the flow of sweat for some patients. Many “clinical strength” over-the- counter antiperspirants contain aluminum salts. Aluminum salt antiperspirants also come in prescription strengths. Apply aluminum salts in the morning and before bedtime to dry skin. If your child experiences skin irritation, try applying every other day.
  • Anticholinergics:
    Anticholinergics block the signals from the nerves to the sweat glands. These medicines may be applied to the skin (creams, lotions, wipes) or taken by mouth. It is important to stay hydrated and avoid overheating while taking these medicines. If you are using a topical for your armpits, be sure to wash hands thoroughly after applying and avoid touching your eyes.
  • Iontophoresis:
    Iontophoresis is used for hand and foot sweating. The hands and/or feet are placed in a tap water bath for approximately 20 minutes at least three times a week. A machine delivers an electrical current to the water.
  • Botulinum toxin:
    Botulinum toxin blocks the signals from the nerve to the sweat glands. Your doctor will inject the medicine directly into affected skin every 6-12 months. Topical anesthesia (ice and/or numbing) helps with the discomfort of this procedure.
  • Other treatments:
    Other treatments such as surgery, microwave technology, and some other newer therapies may also reduce sweating. Not all of these new treatments have been approved for use in children. Discuss risks and benefits with your doctor.

© 2019 The Society for Pediatric Dermatology