Editing Vitamin K (section)

==Vitamin K deficiency==
{{Main|Vitamin K deficiency}}

Because vitamin K aids mechanisms for blood clotting, its deficiency may lead to reduced blood clotting, and in severe cases, can result in reduced clotting, increased bleeding, and increased [[prothrombin time]].<ref name=Higdon /><ref name="DRItext" />

Normal diets are usually not deficient in vitamin K, indicating that deficiency is uncommon in healthy children and adults.<ref name=PKIN2020VitK /> An exception may be infants who are at an increased risk of deficiency regardless of the vitamin status of the mother during pregnancy and breast feeding due to poor transfer of the vitamin to the placenta and low amounts of the vitamin in breast milk.<ref name=Mihatsch2016 />

Secondary deficiencies can occur in people who consume adequate amounts, but have malabsorption conditions, such as [[cystic fibrosis]] or chronic pancreatitis, and in people who have [[liver disease|liver damage or disease]].<ref name=Higdon />  Secondary vitamin K deficiency can also occur in people who have a prescription for a vitamin K antagonist drug, such as warfarin.<ref name=Higdon /><ref name=PKIN2020VitK /> A drug associated with increased risk of vitamin K deficiency is [[cefamandole]], although the mechanism is unknown.<ref>{{cite journal |vauthors=Wong RS, Cheng G, Chan NP, Wong WS, NG MH |title=Use of cefoperazone still needs a caution for bleeding from induced vitamin K deficiency |journal=Am J Hematol |volume=81 |issue=1 |pages=76 |date=January 2006 |pmid=16369967 |doi=10.1002/ajh.20449 |doi-access= }}</ref>