Drug interactions
Estradiol + Nafcillin
Severity: Moderate
Estradiol and Nafcillin: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Nafcillin induces CYP3A4 and may lower estradiol exposure, leading to reduced effect such as breakthrough bleeding or return of menopausal symptoms. The effect is more of a concern for longer courses.
What this interaction means in plain words
Estradiol and Nafcillin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
CYP3A4 induction increases estradiol metabolism.
What to do
Monitor for loss of efficacy during and shortly after nafcillin therapy and increase the estradiol dose if needed. If estradiol is used for contraception, advise backup methods.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Estradiol
- Anastrozole + Estradiol Contraindicated
- Estradiol + Fezolinetant Contraindicated
- Estradiol + Ospemifene Contraindicated
- Antithrombin alfa + Estradiol Major
- Antithrombin iii + Estradiol Major
- Estradiol + Exemestane Major
Frequently asked questions
Can I take Estradiol with Nafcillin?
MediHelp rates the interaction as moderate. Estradiol and Nafcillin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Nafcillin induces CYP3A4 and may lower estradiol exposure, leading to reduced effect such as breakthrough bleeding or return of menopausal symptoms. The effect is more of a concern for longer courses.
How serious is the interaction between Estradiol and Nafcillin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for loss of efficacy during and shortly after nafcillin therapy and increase the estradiol dose if needed. If estradiol is used for contraception, advise backup methods.
What other medicines interact with Estradiol?
MediHelp also lists interactions of Estradiol with, for example, Anastrozole, Fezolinetant, Ospemifene. The full list is on the Estradiol page.
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