2007 ICD-9-CM Procedure 99.27 Iontophoresis Ion transfer of topical solution into the epidermis and mucous membranes of body by continuous direct current. Can be used for local and systemic drug delivery. Concept does not refer to ion exchange, air ionization, and phonophoresis. Therapeutic introduction of ions of soluble salts into tissues by means of electric current. In medical literature it is commonly used to indicate the process of increasing the penetration of drugs into surface tissues by the application of electric current. It has nothing to do with ION EXCHANGE; AIR IONIZATION nor PHONOPHORESIS, none of which requires current. 99.27 is a specific code that can be used to specify a procedure 99.27 contains 4 index entries View the full Volume 3 99.* hierarchy Index entries containing 99.27: Galvanoionization 99.27 Ionization, medical 99.27 Iontherapy 99.27 Iontophoresis 99.27