- While not an exclusion criteria, unless clinically indicated, patients should avoid taking other additional non-study medications that may interfere with the study medications; in particular, patients should avoid medications that are known to either induce or inhibit the activity of hepatic microsomal isoenzymes cytochrome P450, family 1, subfamily A, polypeptide 2 (CYP1A2), cytochrome P450, family 2, subfamily C, polypeptide 19 (CYP2C19) and cytochrome P450, family 3, subfamily A, polypeptide 4 (CYP3A4)