soluble vitamins are provided at levels greater than the RDA since
rapid administration exceeds renal
threshold and therefore increases urinary losses.
soluble vitamins can become toxic, and are provided in amounts equal
to the RDA, except for Vitamin K.
K is not provided because it may interfere with anticoagulant medications.
Vitamin K must be given parenterally or intramuscularly, at a dose
of 2-4 mg/wk, depending on prothrombin time. A long prothrombin
time indicates an increased vitamin K need.
water soluble vitamins can be easily excreted by the kidneys.