Interactions between dutasteride and Erythrocin lactobionate (erythromycin)
erythromycin and dutasteride (Moderate Drug-Drug)
MONITOR: Based on in vitro data, the coadministration with drugs that are inhibitors of the CYP450 3A4 enzymatic pathway may increase the plasma concentrations of dutasteride, which is metabolized by this isoenzyme. No clinical drug interaction studies have been conducted. However, a population pharmacokinetic analysis found decreased clearance of dutasteride when it is coadministered with the CYP450 3A4 inhibitors, verapamil and diltiazem (37% and 44%, respectively). In contrast, no decrease in dutasteride clearance was seen during coadministration with amlodipine, a calcium channel blocker that is not a CYP450 3A4 inhibitor.
MANAGEMENT: The possibility of prolonged and/or increased pharmacologic effects of dutasteride should be considered during chronic, concomitant therapy with CYP450 3A4 inhibitors, particularly potent inhibitors such as ketoconazole, itraconazole, ritonavir, nefazodone and erythromycin.
