Certain milk substitute infant formulas, particularly meat-based and casein hydrolysate based formulas, may be low in vitamin K content in relation to the needs of the infants receiving them. Studies are reviewed of a few infants in which inadequate dietary supply of vitamin K from such sources may have been one factor in the development of hypoprothrombinemia, though this could not be established with certainty.
On theoretical grounds it seems reasonable to increase the level of vitamin K1 in milk substitute formulas to 100 µg/l, particularly because these products are often used in treatment of clinical conditions which are associated with diminished absorption of this vitamin. Vitamin K1 (phylloquinone) would seem the most appropriate form to be used for supplementation of formulas.
In clinical situations associated with malabsorption of fat, e.g., cystic fibrosis of the pancreas or biliary atresia, and prolonged diarrhea or starvation, vitamin K supplementation of feedings or periodic parenteral administration of vitamin K is recommended.
When parenteral vitamin K is necessary, intravenous administration is rarely indicated. Subcutaneous or intramuscular injection is preferred.