What is it?

Hyperhidrosis refers to excessive and uncontrollable sweating. Primary hyperhidrosis usually starts in childhood or adolescence and there may be a family history of hyperhidrosis.

Secondary hyperhidrosis is much less common and can occur from damage to the nervous system or from endocrine disorders including diabetes and hyperthyroidism. There are several medications that can cause hyperhidrosis including, tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRI), nicotinamide, opioids. Alcohol and caffeine can also cause excessive sweating. Hyperhidrosis can be very distressing to patients and have a significant psychosocial impact.

What does it look like?

Hyperhidrosis can be localized or generalized. Localized hyperhidrosis most commonly affects the axilla, palms, and/or soles. Primary hyperhidrosis is generally localized and symmetric. It can be made worse by hot weather, exercise, anxiety and spicy food. Secondary hyperhidrosis is more likely to be unilateral, asymmetric or generalized.

How is it treated?

General measures that can help decrease sweating or the impact of it include wearing loose-fitting and stain-resistant clothing, changing clothing and footwear when it is damp, avoiding caffeinated beverages and alcohol and discontinuing any medications that may be contributing.

Topical antiperspirants such as aluminum chloride in 12-20% solutions are first line in treatment. These are applied nightly to the affected areas until sweating is decreased and then several times weekly for maintenance. The most common side effect is skin irritation, which is worsened by application to damp skin.

If topicals are not sufficient, oral medications such as beta blockers and oral anticholinergic drugs can be trialed. Beta blockers can be used in situations where a patient anticipates having anxiety such as during a presentation. Oral anticholinergics that can be used include oxybutynin or glycopyrrolate, although these may lead to the side effects of dry mouth and eyes, blurry vision, dizziness and constipation.

Iontophoresis devices involve submersion of the affected area in water and application of an electrical current for ~15 minutes. These can be purchased by the patient for home use for hyperhidrosis of the palm or soles and some devices have special pads for axillary use.

Injection of botulinum toxin is often used in the axilla and is very effective, although it is expensive and needs to be repeated approximately every 6 months. It can be used on the palms or soles, but the injections are very painful, and there is a risk of muscle weakness which may interfere with dexterity.

More invasive measures reserved for severe, refractory cases include removal of axillary sweat glands, and sympathectomy.