Nevirapine and Atazanavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Nevirapine
Atazanavir
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Reduced atazanavir exposure, an increased risk of virologic failure, increased nevirapine exposure and an increased risk of nevirapine toxicity
Interaction Deep Dive
Coadministration of atazanavir and nevirapine is contraindicated. Steady-state atazanavir Cmax, AUC, and Cmin decreased significantly and nevirapine Cmax, AUC, and Cmin increased significantly during coadministration in a pharmacokinetic study (N=23). Concurrent use of atazanavir with strong CYP3A4 inducers, such as nevirapine, may reduce the therapeutic effect of atazanavir, possibly leading to virologic resistance3. Furthermore, atazanavir may inhibit the CYP3A4 metabolism of nevirapine, increasing nevirapine plasma concentrations and possibly resulting in toxicity 4312.
Why it happens (mechanism)
Induction of CYP3A4-mediated metabolism of atazanavir; inhibition of CYP3A4-mediated metabolism of nevirapine
Literature reports
1 report — tap to read
a) In a study of patients with HIV infection (n=23), the ratio of geometric means of atazanavir with or with out nevirapine administered 200 mg twice daily for Cmax, AUC, and Cmin were 0.72 (90% CI, 0.6 to 0.86), 0.58 (90% CI, 0.48 to 0.71), and 0.28 (90% CI, 0.2 to 0.4), respectively, for atazanavir with ritonavir 300/100 mg administered once daily; and 1.02 (90% CI, 0.85 to 1.24), 0.81 (90% CI, 0.65 to 1.02), and 0.41 (90% CI, 0.27 to 0.6), respectively, for atazanavir with ritonavir 400/100 mg administered once daily 312. The ratio of geometric means of nevirapine (200 mg administered twice daily) with or without atazanavir for Cmax, AUC, and Cmin were 1.17 (90% CI, 1.09 to 1.25), 1.25 (90% CI, 1.17 to 1.34), and 1.32 (90% CI, 1.22 to 1.43), respectively, for atazanavir with ritonavir 300/100 mg administered once daily; and 1.21 (90% CI, 1.11 to 1.32), 1.26 (90% CI, 1.17 to 1.36), and 1.35 (90% CI, 1.25 to 1.47), respectively, for atazanavir with ritonavir 400/100 mg administered once daily 3.
Common questions
Can I take Nevirapine and Atazanavir together?
Reduced atazanavir exposure, an increased risk of virologic failure, increased nevirapine exposure and an increased risk of nevirapine toxicity Always confirm with your pharmacist or prescriber before making any change.
How serious is the Nevirapine and Atazanavir interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Nevirapine or Atazanavir need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (4)
- Product Information: VIRAMUNE(R) oral suspension, nevirapine oral suspension. Boehringer Ingelheim Pharmaceuticals Inc (per FDA), Ridgefield, CT, 2024. DailyMed
- Product Information: VIRAMUNE XR(R) oral extended-release tablets, nevirapine oral extended-release tablets. Boehringer Ingelheim Pharmaceuticals Inc (per FDA), Ridgefield, CT, 2024. DailyMed
- Product Information: REYATAZ(R) oral capsules, oral powder, atazanavir oral capsules, oral powder. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2020. DailyMed
- Product Information: EVOTAZ(R) oral tablets, atazanavir cobicistat oral tablets. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2023. DailyMed
Keep reading about Nevirapine
Keep reading about Atazanavir
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Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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