An in vivo investigation of the rabbit skin responses to transdermal iontophoresis.
To optimize the benefits of transdermal iontophoresis, it is necessary to develop a suitable animal model that would allow for extensive assessments of the biological effects associated with electro-transport. Rabbit skin responses to iontophoresis treatments were evaluated by visual scoring and by non-invasive bioengineering parameters and compared with available human data. In the current density range 0.1-1.0 mA/cm(2) applied for 1 h using 0.9% w/v NaCl and 0.5 mA/cm(2) for up to 4 h, no significant irritation was observed. 2 mA/cm(2) applied through an area of 1 cm(2) for 1 h resulted in slight erythema at both active electrode sites but without significant changes in transepidermal water loss (TEWL) and laser Doppler velocimetry (LDV). A value of 4 mA/cm(2) under similar conditions caused moderate erythema at the anode and cathode with TEWL and LDV being significantly elevated at both sites; 1 mA/cm(2) current applied for 4 h, caused moderate erythema at both anode and cathode; and 1 mA/cm(2) applied for 1 h caused no irritation when the area of exposure was increased from 1 to 4.5 cm(2). When significant irritation and barrier impairment occurred, the erythema was resolved within 24 h with barrier recovery complete 3-5 days post-treatment. Rabbit skin thus shows promise as an acceptable model for iontophoresis experiments.
Anigbogu
A
A
Department of Dermatology, University of California, 94143-0989, San Francisco, CA, USA.
Patil
S
S
Singh
P
P
Liu
P
P
Dinh
S
S
Maibach
H
H
D000279:Administration, Cutaneous; D000818:Animals; D004553:Electric Conductivity; D017097:Electric Impedance; D005712:Galvanic Skin Response; D006801:Humans; D007478:Iontophoresis / Q000379:methods*; D011817:Rabbits; D012867:Skin / Q000187:drug effects; D012879:Skin Physiological Phenomena