Iontophoresis is a treatment for palmar and plantar hyperhidrosis that uses an electrical current delivered through water to decrease excessive sweating. It is has been used as a treatment for over 70 years and has withstood the test of time. Scientific studies have shown that iontophoresis really does work, doctors regularly prescribe it, and side effects are reported to be mild.[1] However, some patients think that iontophoresis can actually increase their already excessive sweating. Is this true? It is hard to say. It appears on message boards across the internet, new users asking questions like “Can iontophoresis make my sweating worse?” Many users claim that iontophoresis is an effective treatment but admit that it did increase their sweat production when they first started treatment. While this may be the case for some individuals, it does not appear that any studies have specifically looked into the phenomenon. The good news is that most people who claim that iontophoresis did increase their sweating at first say it eventually did lead to a reduction in sweat. So, if you experience increased sweating when you first start iontophoresis keep trying and you will most likely see good results.

Iontophoresis is a mysterious treatment and no one is quite sure how it works. Some theories posit that iontophoresis plugs sweat glands as a result of ion deposition, blocks sympathetic nerve transmission, or decreases the pH of skin as the result of the accumulation of hydrogen ions. At any rate, studies have shown that about 91% of people respond positively to treatment. When side effects do occur during studies they are usually mild and don’t involve an increase in sweat production. The side effects that have been recorded include redness of the skin, small shocks, scratches, cuts, discomfort (feeling of pins and needles), vesiculation, and dry or cracked skin. Many of these side effects are caused by people using iontophoresis incorrectly and often go away after patients learn how to perform iontophoresis correctly. Some people find that iontophoresis doesn't work and there are ways to make it make it more effective. One study that looked at the effectiveness of iontophoresis over time did note that one patient out of 27 experienced a worsening of symptoms between week 3 and week 4 of the experiment.[2] However, the study still demonstrated the effectiveness of iontophoresis over time.

It is not known why some people appear to experience a worsening of symptoms after beginning iontophoresis but it doesn’t seem to impact the effectiveness of the treatment over time. If you experience a worsening of your hyperhidrosis symptoms after starting iontophoresis it is best to talk to your doctor so you can form a plan of action. If iontophoresis does not work for you, there are other effective treatments for for sweaty hands and sweaty feet.

  1. Pariser, D. M. (2014). Hyperhidrosis (4th ed., Vol. 32). Philadelphia, PA: Elsevier.
  2. Kim, D. H., Kim, T. H., Lee, S. H., & Lee, A. Y. (2017). Treatment of Palmar Hyperhidrosis with Tap Water Iontophoresis: A Randomized, Sham-Controlled, Single-Blind, and Parallel-Designed Clinical Trial. Ann Dermatol, 29(6), 728-734. doi:10.5021/ad.2017.29.6.728