Busulfan and Metronidazole interaction
Busulfan and Metronidazole: the Metronidazole prescribing label flags 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 Metronidazole (LIKMEZ) label · effective 2025-04-18
Busulfan : Increased busulfan serum concentrations; avoid concomitant use, monitor for plasma concentrations and adjust the busulfan dose accordingly.
Do not administer LIKMEZ concomitantly with busulfan unless the benefit outweighs the risk.
Busulfan Metronidazole has been reported to increase plasma concentrations of busulfan, which can result in an increased risk for serious busulfan toxicity.
If no therapeutic alternatives to LIKMEZ are available, and concomitant administration with busulfan is medically needed, monitor for busulfan plasma concentrations and adjust the busulfan dose accordingly.
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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.