Percutaneous iontophoresis of prednisolone-a pharmacokinetic study

Percutaneous iontophoresis of 1% prednisolone sodium phosphate through human skin and nail gives peak plasma levels of about one third of that produced by oral ingestion of 10 mg prednisolone. The presence of an epidermal reservoir of steroid was demonstrated by the retention of radio labelled prednisolone in stratum corneum for up to 2 weeks, and a high concentration of prednisolone in whole epidermis (24 h post‐iontophoresis) which was not present 24 h after oral ingestion of prednisolone. The possibility of using this technique for treating diseases of the skin and nails is discussed.