Interactions between methylprednisolone(methylPREDNISolone) and Ru 486 (mifepristone)
methylPREDNISolone and mifepristone (Major Drug-Drug)
GENERALLY AVOID: Mifepristone and corticosteroids may mutually antagonize each other's effects if administered concurrently. Mifepristone is a potent antiglucocorticoid. The efficacy of chronic corticosteroid therapy, including inhaled corticosteroids, may be reduced for 3 to 4 days after mifepristone administration, and the efficacy of mifepristone may be reduced if the corticosteroid is administered systemically or absorbed systemically. Some corticosteroids (e.g., dexamethasone) may also decrease plasma concentrations of mifepristone by inducing its CYP450 3A4 metabolism. In addition, based on in vitro inhibition data, mifepristone may increase the plasma concentrations of corticosteroids by inhibiting their CYP450 3A4 metabolism. Because mifepristone is eliminated slowly from the body, such interactions may be observed for a prolonged period.
MANAGEMENT: Concomitant use of mifepristone and corticosteroids should generally be avoided unless the benefits outweigh the risks. If used concurrently, patients should be monitored for clinical and laboratory evidence of altered efficacy of both drugs. Corticosteroid dose adjustments may be required. Asthmatic patients should be advised to notify their physician if they experience worsening of their respiratory symptoms. The manufacturer of mifepristone considers the drug to be contraindicated in patients on long-term corticosteroid therapy.
