Percutaneous absorption of indomethacin from transparent oil/water gels in rabbits

The percutaneous absorption of indomethacin from transparent oil in water gels (TOW gels) has been studied in rabbits and compared with absorption from a hydrophilic gel and from a spray formulation. The area under the curve and the Cmax values in plasma were significantly higher for the TOW gels in comparison with the other formulations after single application. The pH of the aqueous phase of the TOW gels did not significantly influence the bioavailability. After multiple application the TOW gels induced a larger increase in AUC (vs first application) in comparison with the other formulations. None of the formulations without drug damaged the skin after multiple application. For indomethacin formulations skin damage was more pronounced with the hydrophilic gel than for the TOW gels and spray formulation.