Bismuth subcitrate, metronidazole, and tetracycline and Vardenafil interaction
Bismuth subcitrate, metronidazole, and tetracycline and Vardenafil: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Bismuth subcitrate, metronidazole, and tetracycline (Bismuth Subcitrate Potassium, Metronidazole and Tetracycline Hydrochloride) label · effective 2026-04-13
Drugs that Prolong the QT interval QT prolongation has been reported with metronidazole, a component of bismuth subcitrate potassium, metronidazole and tetracycline hydrochloride, particularly when administered with drugs with the potential for prolonging the QT interval.
From the Vardenafil (Vardenafil Hydrochloride) label · effective 2026-08-27
The interaction is a consequence of blocking hepatic metabolism of vardenafil by ritonavir, a HIV protease inhibitor and a highly strong CYP3A4 inhibitor, which also inhibits CYP2C9.
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.