Sweating is the release of a salty liquid from the body's sweat glands. Sweating or perspiration is important in cooling the body. It is common to sweat under the arms, on the feet, and on the palms of the hands. When the production of sweat is in excess of the amount needed for cooling the body (thermal regulation) it is call hyperhidrosis (excess sweating).
Hyperhidrosis may be primary or secondary. Primary (essential) hyperhidrosis is excess sweating in an otherwise healthy individual.
When excessive sweating affects the hands, feet, and armpits, it's called primary or focal hyperhidrosis. Primary hyperhidrosis affects 2 - 3% of the population. Less than 40% of patients with this condition seek medical advice. In the majority of primary hyperhidrosis cases, no cause can be found. It appears to run in families.
Secondary hyperhidrosis is associated with any number of systemic illnesses. These including pheochromocytoma, thyrotoxicosis, diabetes mellitus, diabetes insipidus, hypopituitarism, anxiety, menopause, carcinoid syndrome, and drug withdrawal. Nocturnal sweating, in particular, may be a clue to the diagnosis of tuberculosis, lymphoma, endocarditis, diabetes, or acromegaly. Treatment of the underlying disease will decrease or cease the excess sweating in secondary hyperhidrosis.
Several common medications occasionally produce hyperhidrosis. These include tricyclic and serotonin reuptake inhibitors, opioid analgesics, acyclovir, and naproxen.
It is important to know if there are any triggers (stress, anxiety, food, etc), if the sweating occurs mostly at night or during the day, which areas of the body are involved, is there an elevated body temperature, or any other problems.
You should see your doctor, if:
* You sweat a lot or if sweating lasts for a long time or can't be explained.
* Sweating occurs with or is followed by chest pain or pressure.
* Sweating is accompanied by weight loss or most often occurs during sleep and associated with a fever.
Treatments for excess sweating may include:
* Antiperspirants. Excessive sweating may be controlled with strong anti-perspirants, which plug the sweat ducts. Products containing 10% to 15% aluminum chloride hexahydrate are the first line of treatment for underarm sweating. Antiperspirants can cause skin irritation. The strong doses of aluminum chloride can damage clothing.
* Medication. Anticholinergics drugs, such as glycopyrrolate (Robinul, Robinul-Forte) are rarely helpful. Beta-blockers or benzodiazepines may help reduce stress-related sweating.
* Iontophoresis. This FDA-approved procedure uses electricity to temporarily turn off the sweat gland. It is most effective for sweating of the hands and feet. The hands or feet are placed into water, and then a gentle current of electricity is passed through it. The electricity is gradually increased until the patient feels a light tingling sensation. The therapy lasts about 10-20 minutes and requires several sessions. Side effects include skin cracking and blisters, although rare.
* Botox. Botulinum toxin type A (Botox) was approved by the FDA in 2004 for the treatment of severe underarm sweating, a condition called primary axillary hyperhidrosis. Small doses of purified botulinum toxin injected into the underarm temporarily block the nerves that stimulate sweating. Side effects include injection-site pain and flu-like symptoms.
* Endoscopic thoracic sympathectomy (ETS). In severe cases, a minimally-invasive surgical procedure called sympathectomy may be recommended. The procedure is usually performed on patients with excessively sweaty palms. It is not as effective on those with excessive armpit sweating. This surgery turns off the signal which tells the body to sweat excessively. ETS surgery is done while the patient is asleep under general anesthesia. The surgery takes about a half hour. Patients usually go home the next day, but may experience pain for about a week. ETS requires special training so make sure your doctor is properly trained. Risks include artery damage, nerve damage, and increased sweating. New sweating occurs in about 50% of patients.
Goldman L, Ausiello D. Cecil Textbook of Medicine, 22nd ed. Philadelphia, Pa: WB Saunders; 2004:2365, 2446-2447.