Vitamin K
A fat-soluble vitamin the body needs to make proteins for blood clotting and for bone and tissue health.
What it is
Vitamin K is a fat-soluble vitamin your body stores in the liver and other tissues, including the brain, heart, pancreas, and bone. It is used to make proteins involved in blood clotting and in maintaining healthy bones and tissues. Most people get enough vitamin K from food, particularly green leafy vegetables and other vegetables; the body can also produce some vitamin K itself.
Food and timing considerations
Vitamin K is fat-soluble and found in foods such as green leafy vegetables and other vegetables. People taking a vitamin K-antagonist blood thinner such as warfarin are specifically advised to keep their day-to-day vitamin K intake consistent rather than avoiding it, since large swings in intake (not vitamin K itself) are what affect how the medication works.
Known interaction categories
- Insufficient evidence
- Use caution
- Monitor
Published interaction pages on this site
Use caution (1)
Monitor (1)
Insufficient evidence (33)
- Vitamin K and AmlodipineInsufficient evidence
- Vitamin K and AshwagandhaInsufficient evidence
- Vitamin K and AspirinInsufficient evidence
- Vitamin K and AtorvastatinInsufficient evidence
- Vitamin K and CaffeineInsufficient evidence
- Vitamin K and CalciumInsufficient evidence
- Vitamin K and CiprofloxacinInsufficient evidence
- Vitamin K and CopperInsufficient evidence
- Vitamin K and CoQ10 (Coenzyme Q10)Insufficient evidence
- Vitamin K and CreatineInsufficient evidence
- Vitamin K and DoxycyclineInsufficient evidence
- Vitamin K and EscitalopramInsufficient evidence
- Vitamin K and Folate / Folic AcidInsufficient evidence
- Vitamin K and IbuprofenInsufficient evidence
- Vitamin K and IronInsufficient evidence
- Vitamin K and LevothyroxineInsufficient evidence
- Vitamin K and LisinoprilInsufficient evidence
- Vitamin K and LosartanInsufficient evidence
- Vitamin K and MagnesiumInsufficient evidence
- Vitamin K and MelatoninInsufficient evidence
- Vitamin K and MetforminInsufficient evidence
- Vitamin K and Omega-3 / Fish OilInsufficient evidence
- Vitamin K and OmeprazoleInsufficient evidence
- Vitamin K and PotassiumInsufficient evidence
- Vitamin K and ProbioticsInsufficient evidence
- Vitamin K and SertralineInsufficient evidence
- Vitamin K and SpironolactoneInsufficient evidence
- Vitamin K and St. John's WortInsufficient evidence
- Vitamin K and TurmericInsufficient evidence
- Vitamin K and Vitamin B12Insufficient evidence
- Vitamin K and Vitamin CInsufficient evidence
- Vitamin K and Vitamin DInsufficient evidence
- Vitamin K and ZincInsufficient evidence
Related guides
Sources
Last reviewed 2026-08-22
Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.