This document discusses vitamin K, including its chemistry, dietary sources, recommended daily intake, role in coagulation, uses, deficiency symptoms, and toxicity. Vitamin K is a fat-soluble vitamin required for blood clotting that exists in multiple forms classified by their side chains. It acts as a cofactor in the liver's production of clotting factors. Green leafy vegetables, liver, and some other foods provide vitamin K, with a recommended daily intake of 50-100 micrograms for adults. Its main role is in late-stage synthesis of coagulation proteins in the liver. Vitamin K deficiency can cause bleeding and is treated with oral or injectable vitamin K supplements.

1. Sathish kumar.R
Altheanz 09

2.  It is a fat soluble dietary principle required for
the synthesis of clotting factors.
Chemistry
◦ Vitamin k has a naphthoquinone ring and a side
chain(R).

3.  Based on the alkyl (R)group vitamin k may be
classified as
K1 – (R-phytyl)
phytonadione
phylloquinone
K2 – (R-prenyl)
menaquinone
K3 – no side chain
menadione
acetamenaphthone

4. DIETARY SOURCE
• Green leafy vegetables such as cabbage,
spinach and liver, cheese,etc…
RDA
 It is uncertain because colonic bacteria itself
produces a variable amount of menaquinone
( vit k2)
 However the total requirement for an adult
has been estimated to be 50-100 µg/day

5. UTILIZATION
 Water soluble vitamin absorb directly into
portal blood.
 Fat soluble vitamins
Absorbed from intestine via lymph
( requires bile salts for absorption)
Temporarily stored in liver
Metabolized by side chain cleavage,
glucuronide conjugation
Metabolites are excreted in bile & urine

6.  Vitamin K has a main role in coagulation
 It acts as a cofactor in late stage of synthesis
of coagulation proteins
( prothrombin, factors vii,ix,x) which are
synthesized by liver as inactive zymogens.

7. Vit K dependent
carboxylase
Warfarin
Dicoumarol
Gamma carboxy glutamic acid
Get bound to phospholipid surfaces
Participate in coagulation
cascade

8.  Vitamin K to a certain extent aids in bone
formation through
gamma carboxylation of osteocalcin
Binds tightly to hydroxy apatite
crystals of bone

9. Only use is in prophylaxis and treatment of
bleeding due to deficiency of clotting
factorsin following situations
 DIETARY DEFICIENCY
Rare but when it occurs 5–10 mg/day oral
or parenteral vitamin K is administered
 PROLONGED ANTIMICROBIAL THERAPHY
 OBSTRUCTIVE JAUNDICE, MALABSORPTION
SYNDROMES
vit K 10mg i.m/day or orally along with
bile salts.

10.  LIVER DISEASES (CIRRHOSIS, VIRAL HEPATITIS)
Vit K may be of some use here
 NEW BORNS
• due to lower capacity to synthesise clotting factors
• Vit K 1mg i.m soon after birth
• Administered 5- 10 mg i.m to mother 4-12 hrs
before delivery
 PROLONGED HIGH DOSE SALICYLATE THERAPY
CAUSING HYPOPROTHROMBINEMIA

11.  OVER DOSE OF ORAL ANTICOAGULANTS
causing hypoprothrombinemia, bleeding
Vitamin K1(phytonadione) is given. It is the
drug of choice because it acts rapidly
 If severe bleeding occurs
• 10 mg i.m followed by 5mg 4 hourly
• Bleeding stops in 6-12 hrs
• But the normal levels of coagulation factors
are restored only after 24 hrs

12. • Hemorrhagic disease of newborn
• Bruising tendency
• Echymotic patients
• Mucous membrane haemorrhage
• Post – traumatic bleeding
• Internal bleeding(GIT, Nose)
• Prolonged clotting,prothrombin time
• haematuria

13.  Rapid i.v injection of emulsified vit K causes
 Flushing
 Breathlessness
 Chest constriction
 Fall in B.P
 manifestations of toxicity are
 Hemolysis
 Hyperbilirubinemia-by competitive inhibition
of glucuronidation
 Kenicterus

14. Thank you