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Warfarin, one of the world's most widely used blood thinners, grew out of a farm mystery: in the 1920s North American cattle bled to death after eating mouldy sweet-clover hay. The cause was dicoumarol, a natural substance that stops blood clotting; research on it produced warfarin, first sold as rat poison.

Wisconsin, 1933

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The story behind the card

In February 1933 a Wisconsin farmer, Ed Carlson, drove about 300 km through a blizzard to the University of Wisconsin in Madison with a dead heifer, a milk can of blood that would not clot and a load of spoiled hay. The biochemist Karl Paul Link took up the problem, and by 1940 his team had isolated the culprit, dicoumarol. A stronger relative they made was named warfarin, after the Wisconsin Alumni Research Foundation that funded the work. It was sold first as rat poison, from 1948, because rats that eat it die of internal bleeding, and was approved for people in 1954. President Eisenhower was treated with it after his 1955 heart attack, which reassured the public. In carefully measured doses it still prevents strokes and dangerous clots in millions of people.

Türkçe oku
Dünyanın en yaygın kan sulandırıcılarından varfarin, bir çiftlik gizeminden doğdu: 1920'lerde Kuzey Amerika'da sığırlar, küflü tatlı yonca samanı yiyip kan kaybından ölüyordu. Sebep, kanın pıhtılaşmasını önleyen dikumarol adlı doğal bir maddeydi; bu madde üzerine yapılan araştırmalar, önce fare zehri olarak satılan varfarini doğurdu.
Wisconsin, 1933

Şubat 1933'te Wisconsin'li çiftçi Ed Carlson, ölü bir düve, pıhtılaşmayan kanla dolu bir süt güğümü ve bir yığın bozuk samanla tipinin içinde yaklaşık 300 kilometre yol yapıp Madison'daki Wisconsin Üniversitesi'ne geldi. Biyokimyacı Karl Paul Link sorunun peşine düştü ve ekibi 1940'a gelindiğinde suçlu maddeyi, dikumarolü ayırmayı başardı. Ekibin ürettiği daha güçlü bir benzerine, çalışmayı finanse eden Wisconsin Alumni Research Foundation'ın baş harflerinden esinlenerek varfarin adı verildi. İlaç 1948'den itibaren önce fare zehri olarak satıldı, çünkü onu yiyen fareler iç kanamadan ölüyordu; 1954'te insanlarda kullanılması onaylandı. Başkan Eisenhower'a 1955'teki kalp krizinden sonra verilmesi halkın güvenini artırdı. Özenle ayarlanmış dozlarda bugün de milyonlarca insanda felci ve tehlikeli pıhtıları önlüyor.

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Background reading: Warfarin
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