Ketoconazole Coadministration of bosentan 125 mg 2 times everyday and ketoconazole, a strong CYP3A inhibitor, increased the plasma concentrations of bosentan by somewhere around 100% in usual volunteers. No dose adjustment of bosentan is necessary, but improved results of bosentan must be considered. We can only refer you to foundations https://franciscovuhtf.activablog.com/25816271/bosentan-an-overview