Medroxyprogesterone and Phenytoin interaction
Medroxyprogesterone and Phenytoin: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Medroxyprogesterone (medroxyprogesterone acetate) label · effective 2026-02-23
Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include: • barbiturates • bosentan • carbamazepine • felbamate • griseofulvin • oxcarbazepine • phenytoin • rifampin • St.
MPA Injectable Suspension, USP can pose an additional risk in patients with risk factors for osteoporosis (e.g., metabolic bone disease, chronic alcohol and/or tobacco use, anorexia nervosa, strong family history of osteoporosis or chronic use of drugs that can reduce bone mass such as anticonvulsants or corticosteroids).
Counsel patients to use a back-up method or alternative method of contraception when enzyme inducers are used with MPA Injectable Suspension, USP.
From the Phenytoin label · effective 2024-12-24
Warfarin Increased and decreased PT/INR responses have been reported when phenytoin is coadministered with warfarin Other Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Anticoagulants Apixaban, dabigatran, edoxaban, rivaroxaban…
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.