The Nobel Prize in Physiology or Medicine 1943 was divided equally between Henrik Carl Peter Dam "for his discovery of vitamin K" and Edward Adelbert Doisy "for his discovery of the chemical nature of vitamin K".

Henrik Dam and Edward A. Doisy received their Nobel Prize one year later, in 1944. During the selection process in 1943, the Nobel Committee for Physiology or Medicine decided that none of the year's nominations met the criteria as outlined in the will of Alfred Nobel. According to the Nobel Foundation's statutes, the Nobel Prize can in such a case be reserved until the following year, and this statute was then applied. Henrik Dam and Edward A. Doisy therefore received their Nobel Prize for 1943 one year later, in 1944.