Increased plasma conc w/ CYP3A inhibitors. Decreased plasma conc w/ strong or moderate CYP3A inducers. Antagonised antiviral effect of ganciclovir & valganciclovir. Risk for lack of efficacy of sensitive CYP1A2 substrates w/ narrow therapeutic window (eg, tizanidine & theophylline). Increased plasma conc of CYP3A/P-gp substrates w/ narrow therapeutic margins (including tacrolimus, cyclosporine, sirolimus & everolimus); sensitive P-gp substrates (eg, digoxin, dabigatran); OAT3 substrates (eg, ciprofloxacin, imipenem, cilastatin). Increased exposure of sensitive BCRP substrates (eg, rosuvastatin).