Blood donors in West Norfolk are now helping to make a new medicine.
As well as their red blood cells being used in the usual way to help save lives, the blood plasma will be taken from each sample and used to make immunoglobulin.
This helps people who struggle to fight infection because of a weak immune system or if they have a condition where the immune system attacks your body.
Immunoglobulin (pictured above) is expensive to buy, and NHS Blood and Transplant says this will help increase its supply.
Around 1700 people across East Anglia were treated with it last year.
*Pictures supplied by NHS Blood and Transplant