Atazanavir and Lopinavir and ritonavir interaction
Atazanavir and Lopinavir and ritonavir: 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 Atazanavir (REYATAZ) label · effective 2024-12-05
…contraindicated with, but not limited to, the following drugs listed in Table 6: Table 6: Drugs Contraindicated with REYATAZ (Information in the table applies to REYATAZ with or without ritonavir, unless otherwise indicated) a See Drug Interactions, Table 16 (7) for parenterally administered midazolam. b See Drug Interactions, Table 16 (7) for sildenafil when dosed…
…within class that are contraindicated with REYATAZ Alpha 1-adrenoreceptor antagonist Alfuzosin Anticonvulsants Carbamazepine, phenobarbital, phenytoin Antiarrhythmics Amiodarone (with ritonavir), quinidine (with ritonavir) Antimycobacterials Rifampin Antineoplastics Apalutamide, encorafenib, irinotecan, ivosidenib Antipsychotics Lurasidone (with ritonavir), pimozide…
Use of REYATAZ without ritonavir is not recommended when coadministered with drugs highly dependent on CYP2C8 with narrow therapeutic indices (eg, paclitaxel, repaglinide).
Antiarrhythmics: amiodarone, quinidine amiodarone, bepridil, lidocaine (systemic), quinidine ↑ amiodarone, bepridil, lidocaine (systemic), quinidine Concomitant use of REYATAZ with ritonavir and either quinidine or amiodarone is contraindicated due to the potential for serious or life-threatening reactions such as cardiac arrhythmias [see Contraindications (4)…
Coadministration with REYATAZ without ritonavir has the potential to produce serious and/or life-threatening adverse events but has not been studied.
From the Lopinavir and ritonavir (Kaletra) label · effective 2026-07-23
The impact on the PR interval of co-administration of KALETRA with other drugs that prolong the PR interval (including calcium channel blockers, beta-adrenergic blockers, digoxin and atazanavir) has not been evaluated.
Potential for KALETRA to Affect Other Drugs Lopinavir/ritonavir is an inhibitor of CYP3A and may increase plasma concentrations of agents that are primarily metabolized by CYP3A.
Although not observed in the KALETRA/ketoconazole drug interaction study, co-administration of KALETRA and other drugs that inhibit CYP3A may increase lopinavir plasma concentrations.
Patients who exhibit these signs or symptoms should be evaluated and KALETRA and/or other antiretroviral therapy should be suspended as clinically appropriate.
Elevated transaminases with or without elevated bilirubin levels have been reported in HIV-1 mono-infected and uninfected patients as early as 7 days after the initiation of KALETRA in conjunction with other antiretroviral agents.
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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.