Stratum corneum reservoir formation after a single topical application of diclofenac

Clijsen, Ron and Clarys, Peter and Lambrecht, Renzo and Barel, André Odilon (2008) Stratum corneum reservoir formation after a single topical application of diclofenac. In: Nationale Kongress des Schweizer Physiotherapie Verbandes, 13-14 June, 2008, St. Gallen, Switzerland.

Full text not available from this repository.


Introduction: The existence of a stratum corneum reservoir has been demonstrated for several topically applied products. Knowledge of the reservoir properties of frequently used products is necessary for the determination of the optimal treatment procedure. It was the aim of this study to determine the reservoir properties of diclofenac after a single topical application with and without occlusion. Methods: Three different groups of 12 healthy volunteers , free of local or systemic treatment with any drugs entered the study. Volunteers were asked to maintain their normal daily activities, but to omit swimming and extensive showering during the duration of the experiments. A commercially available 1% diclofenac (Voltaren Emulgel®, Novartis) formulation was applied on a circular demarcated skin area of 7cm2 on the volar forearms at a concentration of 12mg/cm2. The product was applied under occlusion during 20 minutes. At the same time an open application (same modalities) was performed. Diclofenac stratum corneum bioavailability was assessed using the methyl nicotinate (MN) test. A nicotinate response was performed respectively 90 minutes (group 1), 6 and 24 hours (group 2) and 32 and 48 hours (group 3) after diclofenac application on the diclofenac treated sites but equally at an untreated skin site. The erythema response was quantified with the Minolta Chromameter operating in the L*a* b* mode. Measurements were carried out before diclofenac application, before nicotinate application and every 5 minutes up to 1 hour post nicotinate application. From the measurements in function of time recorded at the different time intervals the area under the response curve was calculated. Areas under the response curve at the different measurements times (respectively at 1.5, 6, 24, 32 and 48 hours post diclofenac application Results: The nicotinate response was suppressed at all measurement intervals (respectively at 1.5, 6, 24, 48 hours). There was no difference between the nicotinate responses at the diclofenac pretreated skin sites when comparing the different measurement times (1.5 versus respectively 6, 24 and 48 hours) neither for the open application (p > 0.05) nor for the application under occlusion (p > 0.05). When comparing the open application with the application under occlusion at the respective measurement times no significant differences were detected (p < 0.05 at all measurement times). Discussion: Our results indicate that even 48 hours after a single 20 minutes application diclofenac is still present in the stratum corneum. A similar response was measured after open application compared to application under occlusion. Occlusion is generally accepted as a penetration enhancing factor. The lack of discrimination between the open diclofenac application and the application under occlusion may be an indication for a diclofenac saturation in the stratum corneum.

Actions (login required)

View Item View Item