天然的维生素K存在于苜蓿、菠菜、西红柿以及鱼糜等内,分别命名为维生素K_1及K_2。人工合成的维生素K为维生素K_3(亚硫酸氢钠甲萘醌)及K_4(乙酰甲萘醌)。目前临床上所用的维生素K为维生素K_1、K_3及K_4,维生素K_1作用较快,持续时间较长,适用于紧急情况;系脂溶性,口服需有胆汁才能吸收。维生素K_3、K_4作用较缓慢,数日后才能发挥疗效,但系水溶性,口服易吸收。 Natural vitamin K exists in alfalfa, spinach, tomatoes and surimi, respectively, named vitamin K_1 and K_2. Synthetic vitamin K for the vitamin K_3 (sodium bisulfite menadione) and K_4 (acetonide). Currently used in clinical vitamin K for vitamin K_1, K_3 and K_4, vitamin K_1 faster, longer duration, suitable for emergency situations; Department of fat-soluble, oral need to have bile to absorb. Vitamin K_3, K_4 role more slowly, a few days later to play a curative effect, but the Department of water-soluble, oral absorption.