Carbidopa, levodopa, and entacapone and Warfarin interaction
Carbidopa, levodopa, and entacapone and Warfarin: the Carbidopa, levodopa, and entacapone 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 Carbidopa, levodopa, and entacapone (Carbidopa, Levodopa and Entacapone) label · effective 2026-04-08
• Drugs metabolized by CYP2C9 (e.g., coumadin): dose adjustment of Carbidopa, levodopa and entacapone tablets may be required; monitor INR when initiating Carbidopa, levodopa and entacapone tablets in patients on coumadin ( 7.11 )
Drugs Metabolized via CYP2C9 (e.g.,coumadin) The dosage of Carbidopa, levodopa and entacapone tablets should be adjusted as clinically needed in patients using other drugs metabolized via CYP2C9.
An interaction study in healthy volunteers, entacapone increased the AUC of R-warfarin on average by 18%, and the INR values on average by 13%.
Cases of increased INR in patients concomitantly using warfarin have been reported during the post-approval use of entacapone.
Thus, monitoring of INR is recommended when Carbidopa, levodopa and entacapone tablets treatment is initiated for patients receiving warfarin.
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.