Drug interactions
Atazanavir + Norethisterone
Severity: Moderate
Atazanavir and Norethisterone: 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
Ritonavir-boosted or unboosted atazanavir raises norethindrone exposure, and boosted regimens may also alter ethinylestradiol. Higher progestin exposure may increase adverse effects, and combined hormonal contraceptive effect becomes less predictable.
What this interaction means in plain words
Atazanavir and Norethisterone 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.
Atazanavir belongs to Anti Virals; Norethisterone belongs to Endocrine.
Why it happens
Atazanavir inhibits CYP3A4 and UGT1A1, reducing norethisterone clearance.
What to do
Review the contraceptive choice and monitor for progestogenic adverse effects. Consider a method without interaction, such as an intrauterine or injectable option.
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 Atazanavir and Norethisterone, 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 Norethisterone
- Acitretin + Norethisterone Contraindicated
- Amobarbital + Norethisterone Major
- Apalutamide + Norethisterone Major
- Belzutifan + Norethisterone Major
- Bosentan + Norethisterone Major
- Brigatinib + Norethisterone Major
Other interactions of Atazanavir
- Alfuzosin + Atazanavir Contraindicated
- Atazanavir + Avanafil Contraindicated
- Atazanavir + Dronedarone Contraindicated
- Atazanavir + Eletriptan Contraindicated
- Atazanavir + Eplerenone Contraindicated
- Atazanavir + Ergotamine Contraindicated
Frequently asked questions
Can I take Atazanavir with Norethisterone?
MediHelp rates the interaction as moderate. Atazanavir and Norethisterone 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. Ritonavir-boosted or unboosted atazanavir raises norethindrone exposure, and boosted regimens may also alter ethinylestradiol. Higher progestin exposure may increase adverse effects, and combined hormonal contraceptive effect becomes less predictable.
How serious is the interaction between Atazanavir and Norethisterone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Review the contraceptive choice and monitor for progestogenic adverse effects. Consider a method without interaction, such as an intrauterine or injectable option.
What other medicines interact with Norethisterone?
MediHelp also lists interactions of Norethisterone with, for example, Acitretin, Amobarbital, Apalutamide. The full list is on the Norethisterone 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.
