Vitamin B12 is given in severe anemia via which route:

Ans. (a) I/MRef. KDT 6th ed. / 588B VITAMIN B12* Present in two forms: cyanocobalamin and hydroxocobalamin.* Dietary sources: liver, kidney, sea fish, egg yolk, meat and cheese.* Only vegetable source: Legumes (pulses)* Daily requirement: 1-2 mg/day. In cases of pregnancy and lactation: 3-5 mg/day.Manifestation of Deficiency* Megaloblastic anemia- the first manifestation.# Hypersegmented neutrophils and giant platelets.* SACD: subacute combined degeneration of spinal cord; peripheral neuritis, paresthesias.* Glossitis, G.I. disturbance: damage to epithelial structures.Preparation Dose and Administration* Cynocobalamin: 35 mg/5ml liquid; 100, 500, 1000 mg Inj.* Hydroxycobalamin: 500, 1000 mg Inj.* Methylcobalamin: 0.5 mg tab.* In case of severe anemia (like pernicious anemia), Vit B12 should be given by I.M or deep s.c (but not by I.V.) injection.* Parenteral administration is necessary to bypass the defective absorptive mechanism.* Hydroxycobalamin has been preferred for parenteral use because of better retention.