Which drugs or supplements interact with estradiol?

Estrogens can inhibit the metabolism of cyclosporine, resulting in increased cyclosporine blood levels. Such increased blood levels can result in kidney and/or liver damage. If this combination cannot be avoided, cyclosporine concentrations can be monitored, and the dose of cyclosporine can be adjusted to assure that its blood levels are not elevated.

Estrogens appear to increase the risk of liver disease in patients receiving dantrolene through an unknown mechanism. Women over 35 years of age and those with a history of liver disease are especially at risk. Estrogens increase the liver’s ability to manufacture clotting factors. Because of this, patients receiving warfarin (Coumadin) need to be monitored for loss of anticoagulant (blood thinning) effect if an estrogen is added when warfarin is already being taken.

Rifampin, barbiturates, carbamazepine (Tegretol), griseofulvin, phenytoin (Dilantin), primidone and St. John’s wort preparations can all increase the elimination of estrogen by enhancing the liver’s ability to metabolize it. Concurrent use may result in reduction of the beneficial effects of estrogens. On the other hand, drugs such as erythromycin, clarithromycin, ketoconazole (Nizoral, Extina, Xolegel, Kuric), itraconazole (Sporanox), ritonavir (Norvir) and grapefruit juice can decrease the liver’s ability to metabolize and eliminate estrogens and may increase the side effects of estrogen.

Estrogens may increase the levels and effects of exogenous corticosteroids (corticosteroids used as drugs that are not produced by the body), ropinirole (Requip, Requip XL), tipranavir (Aptivus) and medications that contain theophylline (Elixophyllin, Theo-24, Theochron).

Estrogens may reduce the levels and the effects of anastrozole (Arimidex), aripiprazole (Abilify), axitinib (Inlyta), hyaluronidase (Amphadase, Hylenex, Vitrase), saxagliptin (Onglyza), somatropin (Genotropin, Humatrope, Norditropen Flexpro etc.), ibrutinib (Imbruvica), and ursodiol (Actigall, Urso 250, Urso Forte).

Estrogen levels and effects may be decreased by dabrafenib (Tafinlar), deferasirox (Exjade), peginterferon Alfa-2b (Peg-Intron, Peg-Intron Redipen, Peg-Intron Redipen Pak 4 and Sylatron), P-glycoprotein inducers, tocilizumab (Actemra) and herbs that belong to a class of medications called CYP3A4 inducers. herbs with contents similar to estrogens may increase the side effects of estrogens.

Estrogen levels and effects may be increased by dehydroepiandrosterone, P-glycoprotein inhibitors, nonsteroidal anti-inflammatory drugs called COX-2 inhibitors such as celecoxib (Celebrex) and ascorbic acid (vitamin C).