Anticoagulants, dietary vitamin

Khan, T. et al. Dietary vitamin K influences intra-individual variability in anticoagulant response to warfarin. Br J Haematol 2004,124 348-354. 

Although antibiotics can inhibit the production of vitamin K in the gut by intestinal bacteria, they do not thereby interfere with the actions of coumarin anticoagulation, since vitamin K that is produced by intestinal bacteria is of less importance than vitamin K that is obtained from dietary sources (178). Nevertheless, there have been... 

Their contents are 34.8 and 53.9 J,g/100g nut, respectively [46], while most other conomonly consumed nuts such as almond, Brazil nut, peanut, and walnut contained < Spg/lOOg. However, the increased consumption of dietary vitamin K could reverse the anticoagulation effect of warfarin, an oral anticoagulant prescribed for primary and secondary prevention of thromboembolic disease, by acting through an alternate enzymatic pathway [47],... 

Booth, S.L., Charnley, J.M., Sadowski, J.A., Saltzman, E., Bovill, E.G., and Cushman, M., Dietary vitamin Ki and stability of oral anticoagulation Proposal of a diet with constant vitamin K, content, Thromb. Haemost., 77, 504-509, 1997. 

Anticoagulants + Dietary supplements Ascorbic acid (Vitamin C)... 

The coumarin and indanedione anticoagulants are vitamin K antagonists, and consequently giving vitamin Kj , (p.458) reduces their effects. The dose at which this might become clinically important is not firmly established, but in one controlled study 150 mierograms of vitamin Kj daily produced a clinically relevant effect in 25% of subjects (see Dietary supplements Vitamin Ki-containing, (p.401)). There is also some evidence that a physicochemical interaction (possibly binding to protein) may occur between warfarin and enteral foods in the gut. ... 

Pedersen FM, Hamberg O, Hess K, Ovesen L. The effect of dietary vitamin K on warfarin-induced anticoagulation. JIntemMed(1991) 229, 517-20. 

Franco V, Polanczyk CA, ClauseU N, Rohde LE. Role of dietary vitamin K intake in chronic oral anticoagulation prospective evidence from observational and randomized protocols. Am... 

Many dietary supplements have antiplatelet activity, which may increase the risk of bleeding when used concurrently with anticoagulants. Feverfew inhibits cyclooxygenase and phospholipase A2 and may interact with anticoagulants and potentiate the antiplatelet effect of aspirin. Other supplements that possess antiplatelet activity include but are not limited to garlic, ginkgo, vitamin E, vitamin A, and selenium. 

Therapeutically, vitamin K is used in prophylaxis and treatment of deficiency of clotting factor due to dietary deficiency of vitamin K, chronic antimicrobial therapy, malabsorption syndrome, obstructive jaundice, liver diseases such as cirrhosis and hepatitis, in neonates to prevent or treat haemorrhagic disease of new born to counteract the overdosing of oral anticoagulants... 

Acquit coagulation defects are more common, and may be due to liver disease (since bile is required for absorption of vitamin K), dietary deficiency of vitamin K, or ingesUon of oral anticoagulant agents. Most of these can be treated by giving vitamin K and its congeners, menadiol sodium phosphate or phytomenadione. 

Sconce E, Khan T, Mason J, Noble F, Wynne H, Kamah F. Patients with unstable control have a poorer dietary intake of vitamin K c cm pared to patients with stable control of anticoagulation Thromb Haemost (2005) 93, 872 5. 

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