INTRAVENOUS USE OF VITAMIN K1 OXIDE

The clinical importance of parenteral therapy with vitamin K has become well established. The most prolonged improvements in prothrombin clotting time so far reported have followed the intravenous administration of either synthetic vitamin K₁ or 2-methyl-1,4-naphthoquinone (menadione). The chemical reactivity and the toxicity of menadione as described by Fieser¹ make it less desirable for general use than vitamin K₁. A single dose of one of these drugs can restore and maintain normal blood prothrombin levels for periods as long as two or three weeks.² Some inconvenience is caused by their lack of solubility in water and their sensitivity to ultraviolet rays. This has led to the continued use of water-soluble preparations; the effects of these are of much shorter duration, so that repeated injection is required for prolonged effect.

After the synthesis of vitamin K₁, Fieser³ postulated that this light-sensitive vitamin probably did not