Described herein are pharmaceutical compositions comprising one or more modulators of a cytochrome 450 enzyme (CYP450) and substituted or unsubstituted diindolylmethane. Also described herein are methods for treating one or more skin conditions by administering a combination therapy comprising substituted or unsubstituted diindolylmethane and one or more modulators of CYP450. In particular, methods are disclosed for improving bioavailability and pharmacokinetic parameters of substituted or unsubstituted diindolylmethane following the combination therapy.
