Drug interactions
Etonogestrel + Griseofulvin
Severity: Moderate
Etonogestrel and Griseofulvin: 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
Enzyme induction by griseofulvin may lower etonogestrel concentrations and reduce contraceptive efficacy of implants or vaginal rings. This raises the risk of unintended pregnancy.
What this interaction means in plain words
Etonogestrel and Griseofulvin 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.
Etonogestrel belongs to Endocrine; Griseofulvin belongs to Anti Fungals.
Why it happens
Griseofulvin induces CYP3A4, increasing the metabolic clearance of etonogestrel.
What to do
Advise a backup barrier contraceptive method during griseofulvin treatment and for about 28 days after stopping. Consider a non-enzyme-affected contraceptive if prolonged therapy is needed.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Etonogestrel and Griseofulvin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Griseofulvin
Other interactions of Etonogestrel
Frequently asked questions
Can I take Etonogestrel with Griseofulvin?
MediHelp rates the interaction as moderate. Etonogestrel and Griseofulvin 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. Enzyme induction by griseofulvin may lower etonogestrel concentrations and reduce contraceptive efficacy of implants or vaginal rings. This raises the risk of unintended pregnancy.
How serious is the interaction between Etonogestrel and Griseofulvin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise a backup barrier contraceptive method during griseofulvin treatment and for about 28 days after stopping. Consider a non-enzyme-affected contraceptive if prolonged therapy is needed.
What other medicines interact with Griseofulvin?
MediHelp also lists interactions of Griseofulvin with, for example, Cyclosporin, Desogestrel-ethinyl estradiol, Dienogest / estradiol valerate. The full list is on the Griseofulvin page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
