Vitamin K Blood Test - More Information

The vitamin K test, also known as a vitamin K lab test, measures the vitamin K blood level.

Vitamin K is a class of vitamins that serve as co-factors in the synthesis of important blood clotting factors in the body. More specifically, vitamin K helps with the production of factors 2, 7, 9 and 10 as well as proteins C and S for blood coagulation. More recent research suggests that vitamin K may also be important for improving bone health, particularly in women with osteoporosis and improving blood vessel elasticity. Vitamin K (particularly the K1 form) can be found in dietary sources such as leafy green vegetables.

Low vitamin K levels can results in abnormal bleeding and can occur from inherited deficiencies, liver dysfunction and intestinal problems from autoimmune conditions or prior surgery. Vitamin K deficiency can also occur with medication use, the most common being warfarin (Coumadin®) which antagonizes the effect of vitamin K. Because of it's relationship with warfarin, the vitamin K test is sometimes ordered along with the INR test. Vitamin K toxicity from high levels is rare and the most common side effect is an allergic reaction.

Getting a vitamin K test near you at a Quest Diagnostics lab is a fairly standard process. After ordering online and selecting your lab, you will get your blood drawn on the day of your lab visit. As can be seen on the sample vitamin K lab report above, the vitamin K blood levels are reported as a number and can be compared against the reference range provided by the lab to get an idea of whether the vitamin K levels would be considered high, normal or low. An 8-12 hour overnight fast is recommended when getting this lab test.