Coadministration has not been studied. Dexamethasone is metabolized by CYP3A4 and concentrations may decrease due to the inducing effect of nevirapine. Nevirapine is metabolized by CYP3A4. Dexamethasone is a dose-dependent inducer of CYP3A4 and is a moderate CYP3A4 inducer at doses above 16 mg. However, dexamethasone is unlikely to alter nevirapine exposure as bosentan (another moderate inducer) had no effect on nevirapine exposure in a drug-drug interaction study. Monitor steroid effect.