Metoprolol and Ritonavir interaction
Metoprolol 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 Metoprolol (Metoprolol Tartrate) label · effective 2026-01-29
CYP2D6 Inhibitors Monitor patients closely when the combination use of CYP2D6 inhibitor and metoprolol cannot be avoided.
CYP2D6 Inhibitors are likely to increase metoprolol concentration.
Drugs that are strong inhibitors of CYP2D6 such as quinidine, fluoxetine, paroxetine, and propafenone were shown to double metoprolol concentrations.
From the Ritonavir (Norvir) label · effective 2026-07-23
The impact on the PR interval of co-administration of ritonavir with other drugs that prolong the PR interval (including calcium channel blockers, beta-adrenergic blockers, digoxin and atazanavir) has not been evaluated.
Initiation of quetiapine in patients taking NORVIR: Refer to the quetiapine prescribing information for initial dosing and titration of quetiapine. β-Blockers: metoprolol, timolol ↑ beta-blockers Caution is warranted and clinical monitoring of patients is recommended.
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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.