Iontophoresis with water has been used since 1952 to treat excessive sweating of the hands and feet. The procedure uses a mild electrical current that is passed through tap water to temporarily shut off sweat glands. A hand and foot is each placed in a different water basin. The electric current is gradually increased to the required level and maintained for 20 minutes before gradually decreasing the current. The procedure is repeated with the other side.
Tap water iontophoresis is generally effective within one month. In one study, 85 percent of patients with excessive perspiration of the palms had normalization of sweating. In another study, patients had an average of 81 percent improvement with treatment. Patients receive three treatments per week until the sweating is controlled (average of 10 treatments). Once sweating normalizes, patients may need as little as one treatment every 2-4 weeks for maintenance. At that point the patient may buy the machine from the manufacturer with a physician's prescription. Insurance does not cover the purchase cost of the machine, usually less than $600.
Side effects are minimal and most patients have no problems with iontophoresis. There is a temporary tingling sensation during and after treatment. A harmless, but uncomfortable electrical shock may occur if the patient suddenly stops treatment (for example by removing a hand). The skin can become too dry and cracked. The dryness is easily treated with moisturizer and less frequent treatments. Occasionally a sunburn-like reaction can occur with redness, and rarely small blisters. If a sunburn-like reaction occurs, topical cortisone creams can help soothe the skin.
Tap water iontophoresis is suitable for almost everybody with excessive sweating on the hands and feet. Patients who have epilepsy, heart problems or cancer should not undergo treatment. In addition this should not be used by patients who have implanted electrical devices or are pregnant.