Compatibility of tacrolimus ointment with corticosteroid ointments of varying potencies

Background: Tacrolimus is often coadministered with various topical corticosteroids in the treatment of steroid-responsive dermatoses; however, the stability of these products in combination has not been examined extensively. Objective: To assess the in vitro compatibility of three tacrolimus-corticosteroid ointment combinations compared with unmixed controls. Methods: Tacrolimus-clobetasol propionate, tacrolimus-desoximetasone, and tacrolimus-hydrocortisone-17-valerate ointment combinations were prepared, stored with unmixed ointments at three temperature/humidity conditions, and evaluated for stability at days 0, 1, 2, 7, 14, and 28 via reverse-phase high-performance liquid chromatography. Results: There was no significant difference in the rate of drug degradation in mixed and unmixed ointments over time or across temperatures for tacrolimus (time p = .94; temperature p = .44), clobetasol (time p = .98, temperature p = .30), desoximetasone (time p = .98; temperature p = .94), or hydrocortisone-17-valerate (time p = .87, temperature p = .36). Limitations: This study did not examine the compatibility of tacrolimus with nonointment formulations. Conclusion: Tacrolimus-clobetasol propionate (superpotent), tacrolimus-desoximetasone (high potent), and tacrolimus-hydrocortisone-17-valerate (midpotent) ointment combinations are chemically compatible for at least 4 weeks.