Atazanavir and Clarithromycin interaction
Atazanavir and Clarithromycin: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Clarithromycin label · effective 2026-01-01
Doses of clarithromycin greater than 1000 mg per day should not be co-administered with protease inhibitors.
Antivirals: Atazanavir Use With Caution Atazanavir: Both clarithromycin and atazanavir are substrates and inhibitors of CYP3A, and there is evidence of a bi-directional drug interaction (see Atazanavir under “Drugs That Affect Clarithromycin Tablets” in the table below) [see Pharmacokinetics ( 12.3 )] .
Antivirals: Atazanavir Use With Caution Atazanavir: When clarithromycin is co-administered with atazanavir, the dose of clarithromycin should be decreased by 50% [see Clinical Pharmacology ( 12.3 )] .
Since concentrations of 14-OH clarithromycin are significantly reduced when clarithromycin is co‑administered with atazanavir, alternative antibacterial therapy should be considered for indications other than infections due to Mycobacterium avium complex.
Clarithromycin and other macrolides are known to inhibit CYP3A and Pgp.
From the Atazanavir (REYATAZ) label · effective 2024-12-05
In addition, concentrations of the active metabolite 14-OH clarithromycin are significantly reduced; consider alternative therapy for indications other than infections due to Mycobacterium avium complex.
Direct-Acting Oral Anticoagulants: betrixaban, dabigatran, edoxaban ↑ betrixaban ↑ dabigatran ↑ edoxaban Concomitant use of REYATAZ with ritonavir, a strong CYP3A4/P-gp inhibitor, may result in an increased risk of bleeding.
Refer to the respective DOAC prescribing information regarding dosing instructions for coadministration with P-gp inhibitors. rivaroxaban REYATAZ with ritonavir ↑ rivaroxaban Coadministration of REYATAZ with ritonavir, a strong CYP3A4/P-gp inhibitor, and rivaroxaban is not recommended, as it may result in an increased risk of bleeding.
Close monitoring is recommended when REYATAZ is coadministered with rivaroxaban. apixaban REYATAZ with ritonavir ↑ apixaban Concomitant use of REYATAZ with ritonavir, a strong CYP3A4/P-gp inhibitor, may result in an increased risk of bleeding.
Macrolide antibiotics: clarithromycin ↑ clarithromycin ↓ 14-OH clarithromycin ↑ atazanavir Increased concentrations of clarithromycin may cause QTc prolongations; therefore, a dose reduction of clarithromycin by 50% should be considered when it is coadministered with REYATAZ.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.