Vitamin K

original designation ("Vit.-K group") only for the naturally occurring K1 and K2 in green plant parts, animal organs, microbial metabolism. Specific effect (hepatic coenzyme function in biosynthesis of coagulation factors) depends on structure and is inhibited by dicumarole →kompetitiv; in hypovitaminosis, e.g. as a result of antibiotic therapy or various diseases, reduction of prothrombin and coagulation factors VII and IX with bleeding tendency.