Cutaneous side-effects of transdermal iontophoresis with and without surfactant pretreatment: a single-blinded, randomized controlled trial.
BACKGROUND
Iontophoresis, a method that facilitates drug transport across skin by an external electrical field, offers the possibility for long-term transdermal delivery of compounds in a well-controlled manner. In general, the literature supports the contention that iontophoresis is a safe procedure. However, there are important medical issues concerning the epidermal and dermal effects of iontophoresis that have not been extensively investigated. Specific and strictly controlled studies on the dermal effect of iontophoresis are scarce.


OBJECTIVE
The aim of this study was to investigate the cutaneous side-effects of transdermal iontophoresis application in healthy human volunteers.


METHODS
This was a single-blinded, randomized and parallel design study. In one group (n=12) subjects were treated nonocclusively with a surfactant formulation followed by iontophoresis (3-h application at a current density of 250 microA cm(-2)). In another group (n=12) iontophoresis alone was performed. No drug was included in these studies. The corresponding passive treatments served as controls. Noninvasive methods including sensation record, transepidermal water loss (TEWL), skin colour and the visual scoring were used to assess cutaneous effects.


RESULTS
Tingling and itching were commonly experienced in the first 30 min of the current application. Iontophoresis in combination with the pretreatment induced significant increases in TEWL values and in skin redness, and resulted in slight to mild erythema and oedema compared with the control. Compared with the iontophoresis alone, the presence of surfactant pretreatment caused slightly more skin irritation (erythema and oedema) but did not further disturb the skin barrier function.


CONCLUSIONS
The transdermal iontophoresis challenges the skin barrier function and induces transient mild skin irritation, but does not cause any permanent damage to the skin when applied for 3 h at a current density of 0.25 mA cm(-2).
Li
G L
GL
Department of Pharmaceutical Technology, University of Leiden, Leiden, the Netherlands.
Van Steeg
T J
TJ
Putter
H
H
Van Der Spek
J
J
Pavel
S
S
Danhof
M
M
Bouwstra
J A
JA
D000328:Adult; D003131:Combined Modality Therapy / Q000379:methods; D004487:Edema / Q000209:etiology; D004890:Erythema / Q000209:etiology; D005260:Female; D006801:Humans; D007478:Iontophoresis / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D012871:Skin Diseases / Q000209:etiology* / Q000503:physiopathology; D012881:Skin Temperature / Q000502:physiology; D013501:Surface-Active Agents / Q000009:adverse effects / Q000627:therapeutic use*; D014870:Water Loss, Insensible / Q000502:physiology
D013501:Surface-Active Agents