Pentoxifylline and Phytonadione (vitamin K1) interaction
Pentoxifylline and Phytonadione (vitamin K1): the Pentoxifylline prescribing label describes 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 Pentoxifylline label · effective 2026-05-15
Increased prothrombin time has been reported in patients concomitantly treated with pentoxifylline and vitamin K antagonists.
Postmarketing cases of increased anticoagulant activity have been reported in patients concomitantly treated with pentoxifylline and vitamin K antagonists.
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.