What Is Iontophoresis?
Iontophoresis (meaning ion transfer) refers to the use of mild electric current for trans-dermal drug delivery (i.e. through the skin)¹. The discovery of iontophoresis dates back to 1747. At the time, it was known that the skin had a selective permeability to lipophilic (lipid soluble) chemicals, and that the skin acted as a barrier to hydrophilic (water soluble) chemicals. This affected the local administration of corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) with regards to the treatment of various musculoskeletal conditions, as these are hydrophilic. Consequently, it was then suggested that hydrophilic drugs might be introduced into the subcutaneous tissue through human skin via the application of a direct current. This brought about what is known today as iontophoresis, a form of trans-dermal drug delivery².