Anastrozole and Estradiol interaction
Anastrozole and Estradiol: the Anastrozole prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Anastrozole (ARIMIDEX) label · effective 2026-03-02
Estrogen Estrogen-containing therapies should not be used with ARIMIDEX as they may diminish its pharmacological action.
• Estrogen-containing products: Combination use may diminish activity of ARIMIDEX.
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.