Effect of Congo Red on Plasma Prothrombin. ∗

Abstract

Summary and Conclusions

The level of plasma prothrombin of mice can be lowered by the addition of mineral oil to the diet. The diminished level of plasma prothrombin can be raised significantly by Congo red and restored to normal by the parenteral administration of 2-methyl-1,4-naphthoquinone. The hemostatic action of Congo red may be explained in some cases, at least in part, by its Vitamin K-like action in raising the plasma prothrombin level.