Dapsone and Atazanavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Atazanavir
Dapsone
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
An increased risk of hemolytic anemia and symptomatic hyperbilirubinemia
Interaction Deep Dive
Coadministration of atazanavir, an inhibitor of CYP3A2 and dapsone, a CYP3A4 substrate, may increase the risk of side effects of dapsone. Concomitant use of an atazanavir-based antiretroviral regimen and dapsone was associated with hemolysis and the development of hyperbilirubinemia resulting in icterus of the sclera in 2 case reports. In both cases symptoms resolved and laboratory parameters normalized following the discontinuation of dapsone 1. If concomitant use is required, consider monitoring for signs and symptoms of hyperbilirubinemia and hemolysis; changes in therapy may be warranted.
Why it happens (mechanism)
Inhibition of CYP3A-mediated dapsone metabolism by atazanavir
Literature reports
1 report — tap to read
a) Hemolytic anemia and symptomatic hyperbilirubinemia with icteric sclera occurred in 2 HIV-infected patients treated with an atazanavir-containing antiretroviral regimens and concurrent dapsone for Pneumocystis pneumonia prevention. The first patient, a 38-year-old woman, developed persistent yellowing of the sclera shortly after initiation of dapsone. Viral hepatitis and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were ruled out, but blood tests revealed normocytic anemia (Hb 9.7 mg/dL), an unconjugated bilirubin level of 6.6 mg/dL, and evidence of hemolysis was noted later. The second patient, a 55–year-old man, developed icteric sclera 1 to 2 weeks after simultaneous initiation of an atazanavir-containing antiretroviral regimen and dapsone. Laboratory analysis revealed evidence of hemolysis, normocytic anemia (Hb 11.1 mg/dL), and an unconjugated bilirubin level of 6.3 mg/dL, and viral hepatitis and G-6-PD deficiency were ruled out. In both cases, icterus resolved and laboratory values normalized following the discontinuation of dapsone 1.
Common questions
Can I take Dapsone and Atazanavir together?
An increased risk of hemolytic anemia and symptomatic hyperbilirubinemia Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dapsone and Atazanavir interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
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 "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Dapsone 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 anything you'd monitor while I'm on both?
References (2)
- East J & Blanton LS: Symptomatic hyperbilirubinemia secondary to dapsone-induced hemolysis and atazanavir therapy. Antimicrob Agents Chemother 2012; 56(2):1081-1083. PubMed
- Product Information: REYATAZ(R) oral capsules, atazanavir sulfate oral capsules. Bristol-Myers Squibb (per Manufacturer), Princeton, NJ, 2012. DailyMed
Keep reading about Atazanavir
Keep reading about Dapsone
These medications also interact with supplements
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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