Belzutifan is often a CYP2C19 substrate. Coadministration with CYP2C19 inhibitors could improve incidence or severity of adverse outcomes. Keep track of for anemia and hypoxia and minimize belzutifan dose as proposed.No certain dose adjustment proposed when tofacitinib coadministered with potent CYP2C19 inhibitors; lower tofacitinib dose if coadmin