Supplement × Prescription·Evidence index
PubMed indexes 8 records that name Vitamin K1 and Warfarin together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.
Every statement below is attributed to a named, dated, linked source.
This page lists published research relevant to Vitamin K1 and Warfarin. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“In patients receiving warfarin therapy who have an increased INR and are at risk of bleeding, oral vitamin K1 therapy may be safer, less painful, and more cost-effective than the traditional parenteral route of administration.”
Names both Vitamin K1 and Warfarin in its title.
Names both Vitamin K1 and Warfarin in its title.
“Following the administration of vitamin K1, the maximum plasma concentration and area under the plasma concentration time curve values for the metabolite vitamin K1 2,3-epoxide were greater after S warfarin than after R warfarin. The greater anticoagulant potency of S warfarin is reflected by a greater degree of inhibition of vitamin K1 epoxide reductase.”
Names both Vitamin K1 and Warfarin in its title.
“The therapeutic response time, without supportive therapy, after discontinuation of warfarin administration was 30 hours, and there was a PT reversal time of approximately 5 days from the last dose of warfarin. The 100-mg dose of vitamin K1 shortened the therapeutic response time to 12 hours and the PT reversal time to 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS)”
Names both Vitamin K1 and Warfarin in its title.
“5. The anti-inflammatory effect of both sodium warfarin and of vitamin K1 in rats, is not interfered with by previous adrenalectomy.”
Names both Vitamin K1 and Warfarin in its title.
Names both Vitamin K1 and Warfarin in its title.
“Restriction of dietary vitamin K intake does not seem to be a valid strategy to improve anticoagulation quality with VKAs. It would be, perhaps, more relevant to maintain stable dietary habit, avoiding wide changes in the intake of vitamin K.”
Names Vitamin K1 and Warfarin together in an interaction, co-administration, or pharmacokinetic context.
“In contrast to warfarin, BDF has an extremely long-acting biological half-life of 90 days due to minimal metabolism and limited clearance. Here, we report a 45-year-old male who presented to the emergency room with a 12-day history of gross hematuria and mucosal bleeding without previous history of coagulopathy and recurrent SCs use.”
Names Vitamin K1 and Warfarin together in an interaction, co-administration, or pharmacokinetic context.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Vitamin K1, Warfarin, and several hundred other substances.
The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
