Treatment of palmoplantar hyperhidrosis was carried out with a conventional galvanic generator in 40 patients and with a newly developed iontophoresis apparatus, which is suited for home treatment, in 31 patients. The new apparatus is operated by a rechargeable energy source or by batteries and is disconnected from the electrical net during treatment. It conforms to most recent safety regulations as approved by Underwriter's Laboratory. Hyperhidrosis was completely controlled after 10-12 treatments as revealed by quantitative gravimetric measurements of sweat rates and semiquantitative estimation of starch iodine paper imprints. There was no apparent difference in efficacy between the two apparatuses. Not only hyperhidrosis was abolished, but associated symptoms, such as lividity of palms or soles, acral hypothermia and edema of fingers or toes, also subsided. Skin temperature on palms rose from 29.7 +/- 1.8 degrees C before treatment to 32.2 +/- 1.4 degrees C thereafter. Maintenance treatment was continued on an average for 14 months, in 4 patients for more than 3 years. No loss of efficacy was found during that period. Side effects were minimal and depended upon amperage used. Only slight discomfort during treatment and mild short-lasted skin irritation were observed. Long-term side effects did not occur.