Vitamin KVitamin K comes from dietary sources such as leafy green vegetables, liver,
cheese, and egg yolk and is synthesized by intestinal flora. Vitamin K is required
to synthesize prothrombin and clotting factors VII, IX, and X and is an antidote
for oral overdose of the anticoagulant Coumadin (Warfarin). There are four forms
of Vitamin K: K 1 (phytonadione), which is the active form; K 2 (menaquinone),
which is synthesized by intestinal flora, but not commercially available; K 3 (mena-
dione) and K 4 (menadiol), both of which are produced synthetically. K 1 and K 2 are
absorbed in the presence of bile salts. K 3 and K 4 are absorbed without bile salts.
Vitamin K 1 prevents hemorrhage and is available as Mephyton, AquaMEPHYTON,
and Konakion. Vitamin K 4 is available as Synkayvite. Vitamin K is absorbed in
the intestines and is stored in the liver and in other tissues.
Water-soluble vitamins
Water-soluble vitamins are also known as the B Complex because it was origi-
nally considered as one vitamin. It was later discovered that these are separate
vitamins. The following are water-soluble vitamins.
CHAPTER 9 Vitamins and Minerals^143
Dose for treatment 5–15 mg/d (based on prothrombin time [PT] laboratory results)
of deficiency
Maintenance Male: 70–80 μ g/day
Female: 60–65 μ g/day
If taking a broad-spectrum antibiotic: 140 μ g/day
Pregnancy: 65 μ g/day
Pregnancy category C
Deficiency conditions Increased clotting time leading to increased bleeding and hemorrhage
Side effects Occasional pain, soreness, and swelling at IM injection site; pruritic
erythema (itchy redness) with repeated injections; flushed face,
unusual taste.
Adverse reactions Rare: severe reaction immediately following IV administration
(cramplike pain, chest pain, dyspnea, facial flushing, dizziness,
rapid/weak pulse, rash, profuse sweating, hypotension; may
progress to shock, cardiac arrest)
Contraindications Last few weeks of pregnancy and in neonates; Use with caution:
asthma and impaired hepatic functionVitamin K