Fluorouracil and Tinidazole interaction
Fluorouracil and Tinidazole: the Tinidazole 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 Tinidazole label · effective 2025-12-01
If the concomitant use of tinidazole and fluorouracil cannot be avoided, the patient should be monitored for fluorouracilassociated toxicities.
Fluorouracil: Monitor for fluorouracil-associated toxicities ( 7.1 )
Fluorouracil: Metronidazole was shown to decrease the clearance of fluorouracil, resulting in an increase in side-effects without an increase in therapeutic benefits.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.