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Vitamin K Excess

(Vitamin K Toxicity)

By

Larry E. Johnson

, MD, PhD, University of Arkansas for Medical Sciences

Last full review/revision Nov 2020
CLICK HERE FOR THE PROFESSONAL VERSION

Vitamin K toxicity is rare but is most common in formula-fed infants. 

Vitamin K has two forms:

  • Phylloquinone: This form occurs in plants and is consumed in the diet. It is absorbed better when it is consumed with fat. Phylloquinone is not toxic, even in large amounts.

  • Menaquinone: This form is produced by bacteria in the intestine, but only small amounts of it are produced. In some countries, this form is used for supplementation.

Vitamin K is necessary for normal blood clotting. It is also needed for healthy bones and other tissues.

Drugs Mentioned In This Article

Generic Name Select Brand Names
DRISDOL
No US brand name
NIACOR, NIASPAN
DURLAZA
LANIAZID
No US brand name
CUPRIMINE
COUMADIN
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSONAL VERSION
CLICK HERE FOR THE PROFESSONAL VERSION
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