Vitamin K1 is a yellow, clear and viscous oily liquid with low price and fewer adverse reactions. Vitamin K2 has various forms, and currently the State Food and Drug Administration (CFDA) has not approved its listing. Vitamin K3 can interfere with the function of glutathione, and it has been confirmed that high-dose vitamin K3 can cause allergic reactions, hemolytic anemia, hepatotoxicity, etc. It is no longer used as a supplement for vitamin K. The absorption of vitamin K4 does not require the assistance of bile, and it can be used as a substitute for patients with related diseases caused by insufficient bile secretion and vitamin K absorption disorders. At present, vitamin K1 preparations are mainly used in clinical practice.

Indications
1. Hemorrhage caused by vitamin K deficiency, such as obstructive jaundice, biliary fistula, chronic diarrhea, etc;
2. Hypothrombotoxinemia caused by coumarins, sodium salicylate, etc;
3. Neonatal bleeding;
4. Vitamin K deficiency in the body caused by long-term use of broad-spectrum antibiotics.
pharmacological action 
Vitamin K1 is a yellow, clear and viscous oily liquid. Vitamin K1 is a fat soluble vitamin. Vitamin K is an essential substance for the synthesis of prothrombin in the liver, and its function is to promote the transformation of prothrombin precursors into prothrombin. When lacking, it can cause hypothrombinemia and lead to coagulation disorders. Vitamin K1 is mainly used to prevent and treat bleeding caused by vitamin K deficiency.
1. Participate as a cofactor in the synthesis of coagulation factors II, VII, XII, and X.
2. Promote the conversion of fibrinogen into fibrin, improve the elasticity of plasma fibrin clots.
3. It is necessary to participate in the oxidation process to ensure the transfer of phosphate radicals and the normal metabolism of high-energy phosphate compounds in the body.
4. Increase intestinal peristalsis and secretion function, and increase the tension of the common bile duct sphincter.
purpose
Vitamin K1, as a pharmaceutical preparation, is used in clinical practice for the prevention and treatment of thrombocytopenia, vitamin K1 deficiency, neonatal spontaneous bleeding, as well as bleeding caused by obstructive jaundice, biliary fistula, chronic diarrhea, and low prothrombin blood caused by coumarins, sodium salicylate, etc. Vitamins also have analgesic and relieving effects on bronchospasm, and have a significant effect on colic caused by visceral smooth muscle spasm, bile duct spasm, and intestinal spasm. Vitamin K1 can also be used as an additive in multidimensional food and livestock feed.
Adverse reactions
There were no adverse reactions at commonly used doses. During intramuscular injection, there is pain at the injection site. Intravenous injection of tachycardia can cause flushing, sweating, bronchospasm, chest pain, tachycardia, and even hypotension, shock, and there have been reports of death.