Methylergonovine and Mifepristone interaction

Although there have been no reports of such interactions with methylergonovine alone, strong and moderate CYP 3A4 inhibitors should not be co-administered with methylergonovine.

Weak CYP 3A4 inhibitors should be administered with caution.

Drug Interactions CYP 3A4 Inhibitors (e.g., Macrolide Antibiotics and Protease Inhibitors) There have been rare reports of serious adverse events in connection with the coadministration of certain ergot alkaloid drugs (e.g., dihydroergotamine and ergotamine) and potent CYP 3A4 inhibitors, resulting in vasospasm leading to cerebral ischemia and/or ischemia of…

Examples of some of the strong CYP 3A4 inhibitors include saquinavir, grapefruit juice, nefazodone, macrolide antibiotics (e.g., troleandomycin, clarithromycin), HIV protease or reverse transcriptase inhibitors (e.g., ritonavir, indinavir, nelfinavir) or azole antifungals (e.g., ketoconazole, itraconazole, voriconazole).

…, 8.3 )] Patients taking drugs metabolized by CYP3A such as simvastatin, lovastatin, and CYP3A substrates with narrow therapeutic ranges, such as cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus, due to an increased risk of adverse events. [See Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.3 )]…

…the increased risk of myopathy and rhabdomyolysis. [See Contraindications (4.2), Clinical Pharmacology 12.3 ] The exposure of other substrates of CYP3A with narrow therapeutic ranges, such as cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus, may be increased by concomitant administration with mifepristone.