title: Transdermal delivery of indomethacin by iontophoresis.
abstract: The objective of this study was to construct a modified equation for the delivery of a drug by iontophoresis. Indomethacin was selected as a model since it has been widely used as a non-steroidal anti-inflammatory drug (NSAID) for external pharmaceutical preparations. The experiments were performed under a constant current in vivo using rat abdominal skin, and the plasma concentration was monitored by HPLC. Pharmacokinetic parameters were obtained from the plasma concentration profiles after intravenous injection. A theoretical value of the transdermal delivery of drug by iontophoresis was calculated from the plasma concentration and pharmacokinetic parameters. The experimental value was evidently higher than the theoretical one, suggesting the enhancement of passive diffusion with an increase of applied current. The modified equation was proposed for the delivery of a drug by iontophoresis incorporating enhanced passive diffusion.
authors.affiliation: Fuji Research Laboratories, Pharmaceutical Division, Kowa Company, LTD, Shizuoka, Japan. m-kanebk@kowa.co.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Kanebako
authors.forename: Toshio
authors.initials: T
authors.lastname: Inagi
authors.forename: Kozo
authors.initials: K
authors.lastname: Takayama
mesh_terms: D000279:Administration, Cutaneous; D000465:Algorithms; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid; D016503:Drug Delivery Systems; D007213:Indomethacin / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D008297:Male; D008970:Molecular Weight; D051381:Rats; D017208:Rats, Wistar; D012869:Skin Absorption
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007213:Indomethacin