The human body contains a complex clotting system that helps to control bleeding. Many of the compounds within this system are dependent on vitamin K for synthesis. Unfortunately, certain factors that can alter vitamin K levels can inhibit the production of these coagulation factors. This is especially important in patients taking anticoagulants such as warfarin since a reduction in vitamin K can increase the risk of bleeds.
Warfarin
Warfarin is the generic name for a prescription medication used to inhibit the formation of blood clots. Warfarin works by inhibiting the synthesis of coagulation factors that are dependent on vitamin K. Routine monitoring of the International Normalized Ratio, or INR, a measurement of clotting time, is required for patients on warfarin therapy. Since warfarin has a narrow therapeutic range, a reduction in vitamin K can increase the risk of bleeding.
Vitamin K
Vitamin K is a fat-soluble vitamin that can be obtained from the diet. In addition, vitamin K is also synthesized by certain bacteria that are found as part of the normal intestinal flora. Within the coagulation pathway, vitamin K is required for the synthesis of coagulation factors II, VII, IX, and X. Conditions that reduce vitamin K can cause lower production of dependent coagulation factors.
Changes in Diet
According to the Linus Pauling Institute, foods that contain a high content of vitamin K include green leafy vegetables such as spinach, parsley, and broccoli. Individuals who alter their diet to include lower amounts of these foods can experience a reduction in the availability of vitamin K. Patients on warfarin therapy are encouraged to keep a consistent diet and to notify their health care provider if any changes to their diet plan are made.
Diarrhea
Another major factor that can lower vitamin K levels is the presence of diarrhea. Persistent diarrhea can affect the absorption of dietary vitamin K. In addition, diarrhea is often caused by infections that can alter the balance of intestinal flora, including bacteria that produce vitamin K. The use of antibiotics can also alter intestinal flora. Patients on warfarin therapy should contact their health care providers if they experience persistent diarrhea, since they may require more routine monitoring of INR.
Member Comments