Drug interactions
Etonogestrel + St john's wort
Severity: Major
Etonogestrel and St john's wort: major interaction.
Last updated Sources: US FDA label
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
St John's wort induces drug metabolism and may lower progestin levels, with reports of breakthrough bleeding and unintended pregnancy with hormonal contraceptives. Reliability of the implant or ring may be reduced.
What this interaction means in plain words
Etonogestrel and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Hyperforin activates PXR, inducing CYP3A4 and P-glycoprotein and increasing etonogestrel clearance.
What to do
Advise stopping St John's wort, or use additional non-hormonal contraception during use and for about four weeks after stopping.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Etonogestrel
Frequently asked questions
Can I take Etonogestrel with St john's wort?
MediHelp rates the interaction as major. Etonogestrel and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. St John's wort induces drug metabolism and may lower progestin levels, with reports of breakthrough bleeding and unintended pregnancy with hormonal contraceptives. Reliability of the implant or ring may be reduced.
How serious is the interaction between Etonogestrel and St john's wort?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise stopping St John's wort, or use additional non-hormonal contraception during use and for about four weeks after stopping.
What other medicines interact with Etonogestrel?
MediHelp also lists interactions of Etonogestrel with, for example, Amobarbital, Armodafinil, Bosentan. The full list is on the Etonogestrel page.
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