Drug interactions
Etonogestrel + Nelfinavir
Severity: Moderate
Etonogestrel and Nelfinavir: 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
Nelfinavir can alter progestin exposure, and labeling for HIV protease inhibitors describes changes in hormonal contraceptive levels. Contraceptive efficacy may become less reliable, and progestin-related adverse effects may also change.
What this interaction means in plain words
Etonogestrel and Nelfinavir 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; Nelfinavir belongs to Anti Virals.
Why it happens
Nelfinavir modulates CYP3A4 metabolism of etonogestrel; its net effect on hormone exposure is variable and may include induction.
What to do
Advise an additional barrier contraceptive method while on nelfinavir and for a short period after stopping, or choose a non-hormonal method such as a copper IUD. Review the contraceptive plan with the HIV specialist.
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 Etonogestrel
Other interactions of Nelfinavir
- Alfuzosin + Nelfinavir Contraindicated
- Avanafil + Nelfinavir Contraindicated
- Dronedarone + Nelfinavir Contraindicated
- Eletriptan + Nelfinavir Contraindicated
- Ergotamine + Nelfinavir Contraindicated
- Flibanserin + Nelfinavir Contraindicated
Frequently asked questions
Can I take Etonogestrel with Nelfinavir?
MediHelp rates the interaction as moderate. Etonogestrel and Nelfinavir 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. Nelfinavir can alter progestin exposure, and labeling for HIV protease inhibitors describes changes in hormonal contraceptive levels. Contraceptive efficacy may become less reliable, and progestin-related adverse effects may also change.
How serious is the interaction between Etonogestrel and Nelfinavir?
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 an additional barrier contraceptive method while on nelfinavir and for a short period after stopping, or choose a non-hormonal method such as a copper IUD. Review the contraceptive plan with the HIV specialist.
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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