atazanavir and nevirapine: what the product label says

The product label for nevirapine names atazanavir in its drug-interaction information. The complete selected section is reproduced below so that qualifications stay with the finding.

Which products this evidence covers

Nevirapine — TABLET — ORAL

Labeled active ingredients: NEVIRAPINE. Routes: ORAL. Dosage forms: TABLET.

Supporting label passage

Section: 7 DRUG INTERACTIONS

Nevirapine is principally metabolized by the liver via the cytochrome P450 isoenzymes, 3A and 2B6. Nevirapine is known to be an inducer of these enzymes. As a result, drugs that are metabolized by these enzyme systems may have lower than expected plasma levels when co-administered with nevirapine. The specific pharmacokinetic changes that occur with co-administration of nevirapine and other drugs are listed in Clinical Pharmacology , Table 5. Clinical comments about possible dosage modifications based on established drug interactions are listed in Table 4. The data in Tables 4 and 5 are based on the results of drug interaction trials conducted in HIV-1 seropositive subjects unless otherwise indicated. In addition to established drug interactions, there may be potential pharmacokinetic interactions between nevirapine and other drug classes that are metabolized by the cytochrome P450 system. These potential drug interactions are also listed in Table 4. Although specific drug interaction trials in HIV-1 seropositive subjects have not been conducted for some classes of drugs listed in Table 4, additional clinical monitoring may be warranted when co-administering these drugs. The in vitro interaction between nevirapine and the antithrombotic agent warfarin is complex. As a result, when giving these drugs concomitantly, plasma warfarin levels may change with the potential for increases in coagulation time. When warfarin is co-administered with nevirapine, anticoagulation levels should be monitored frequently. Table 4 Established and Potential Drug Interactions: Use with Caution, Alteration in Dose or Regimen May Be Needed Due to Drug Interaction Established Drug Interactions: See Clinical Pharmacology (12.3), Table 5 for Magnitude of Interaction. * The interaction between nevirapine and the drug was evaluated in a clinical study. All other drug interactions shown are predicted. Drug Name Effect on Concentration of Nevirapine or Concomitant Drug Clinical Comment HIV Antiviral Agents: Protease Inhibitors (PIs) Atazanavir/Ritonavir* ↓ Atazanavir ↑ Nevirapine Do not co-administer nevirapine with atazanavir because nevirapine substantially decreases atazanavir exposure and there is a potential risk for nevirapine-associated toxicity due to increased nevirapine exposures. Fosamprenavir* Fosamprenavir/Ritonavir* ↓Amprenavir ↑Nevirapine ↓Amprenavir ↑Nevirapine Co-administration of nevirapine and fosamprenavir without ritonavir is not recommended. No dosing adjustments are required when nevirapine is co-administered with 700/100 mg of fosamprenavir/ritonavir twice daily. The combination of nevirapine administered with fosamprenavir/ritonavir once daily has not been studied. Indinavir* ↓ Indinavir The appropriate doses of this combination of indinavir and nevirapine with respect to efficacy and safety have not been established. Lopinavir/Ritonavir* ↓Lopinavir Dosing in adult patients: A dose adjustment of lopinavir/ritonavir to 500/125 mg tablets twice daily or 533/133 mg (6.5 mL) oral solution twice daily is recommended when used in combination with nevirapine. Neither lopinavir/ritonavir tablets nor oral solution should be administered once daily in combination with nevirapine. Dosing in pediatric patients: Please refer to the Kaletra ® prescribing information for dosing recommendations based on body surface area and body weight. Neither lopinavir/ritonavir tablets nor oral solution should be administered once daily in combination with nevirapine. Nelfinavir* ↓Nelfinavir M8 Metabolite ↓Nelfinavir C min The appropriate doses of the combination of nevirapine and nelfinavir with respect to safety and efficacy have not been established. Saquinavir/Ritonavir The interaction between nevirapine and saquinavir/ritonavir has not been evaluated The appropriate doses of the combination of nevirapine and saquinavir/ritonavir with respect to safety and efficacy have not been established. HIV Antiviral Agents: Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) Efavirenz* Etravirine Rilpivirine ↓ Efavirenz The appropriate doses of these combinations with respect to safety and efficacy have not been established. Plasma concentrations may be altered. Nevirapine should not be co-administered with another NNRTI as this combination has not been shown to be beneficial. Other Agents Analgesics: Methadone* ↓ Methadone Methadone levels were decreased; increased dosages may be required to prevent symptoms of opiate withdrawal. Methadone-maintained patients beginning nevirapine therapy should be monitored for evidence of withdrawal and methadone dose should be adjusted accordingly. Antiarrhythmics: Amiodarone, disopyramide, lidocaine Plasma concentrations may be decreased. Appropriate doses for this combination have not been established. Antibiotics: Clarithromycin* Rifabutin* Rifampin* ↓ Clarithromycin ↑ 14-OH clarithromycin ↑Rifabutin ↓ Nevirapine Clarithromycin exposure was significantly decreased by nevirapine; however, 14-OH metabolite concentrations were increased. Because clarithromycin active metabolite has reduced activity against Mycobacterium avium-intracellulare complex , overall activity against this pathogen may be altered. Alternatives to clarithromycin, such as azithromycin, should be considered. Rifabutin and its metabolite concentrations were moderately increased. Due to high intersubject variability, however, some patients may experience large increases in rifabutin exposure and may be at higher risk for rifabutin toxicity. Therefore, caution should be used in concomitant administration. Nevirapine and rifampin should not be administered concomitantly because decreases in nevirapine plasma concentrations may reduce the efficacy of the drug. Physicians needing to treat patients co-infected with tuberculosis and using a nevirapine-containing regimen may use rifabutin instead. Anticonvulsants: Carbamazepine, clonazepam, ethosuximide Plasma concentrations of nevirapine and the anticonvulsant may be decreased. Use with caution and monitor virologic response and levels of anticonvulsants. Antifungals: Fluconazole* Ketoconazole* Itraconazole ↑Nevirapine ↓ Ketoconazole ↓ Itraconazole Because of the risk of increased exposure to nevirapine, caution should be used in concomitant administration, and patients should be monitored closely for nevirapine-associated adverse events. Nevirapine and ketoconazole should not be administered concomitantly because decreases in ketoconazole plasma concentrations may reduce the efficacy of the drug. Nevirapine and itraconazole should not be administered concomitantly due to potential decreases in itraconazole plasma concentrations that may reduce efficacy of the drug. Antithrombotics: Warfarin Plasma concentrations may be increased. Potential effect on anticoagulation. Monitoring of anticoagulation levels is recommended. Calcium Channel blockers: Diltiazem, nifedipine, verapamil Plasma concentrations may be decreased. Appropriate doses for these combinations have not been established. Cancer Chemotherapy: Cyclophosphamide Plasma concentrations may be decreased. Appropriate doses for this combination have not been established. Ergot Alkaloids: Ergotamine Plasma concentrations may be decreased. Appropriate doses for this combination have not been established. Immunosuppressants: Cyclosporine, tacrolimus, sirolimus Plasma concentrations may be decreased. Appropriate doses for these combinations have not been established. Motility Agents: Cisapride Plasma concentrations may be decreased. Appropriate doses for this combination have not been established. Opiate Agonists: Fentanyl Plasma concentrations may be decreased. Appropriate doses for this combination have not been established. Oral Contraceptives: Ethinyl estradiol and Norethindrone* ↓ Ethinyl Estradiol ↓ Norethindrone Despite lower ethinyl estradiol and norethindrone exposures when co-administered with nevirapine, literature reports suggest that nevirapine has no effect on pregnancy rates among HIV-infected women on combined oral contraceptives. When co-administered with nevirapine, no dose adjustment of ethinyl estradiol or norethindrone is needed when used in combination for contraception. When these oral contraceptives are used for hormonal regulation during nevirapine therapy, the therapeutic effect of the hormonal therapy should be monitored.

Read the full product label on DailyMed. Label version 10, dated 2026-10-08.

Limits of this evidence

This passage applies to the labeled product and circumstances it describes. It must not be generalized to other routes or formulations. It does not independently validate CDI’s severity category, establish safety for an individual, or replace the full label. The stored interaction description and classification have not been changed by this article.

How this brief was prepared

Automatic checks matched drug identities, retrieved and preserved the label, and checked the full quoted section with AI assistance on 2026-11-11. The public explanation uses a fixed template; model-written medical advice is not published. Independent clinical review has not been recorded.

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