Is there a universal blood donor type?

Answer From Rajiv K. Pruthi, M.B.B.S.

People who need to get donor red blood cells right away, called an emergency transfusion, most often get blood group type O blood. This type of blood has the lowest risk of causing serious reactions when there isn't time to do routine testing. Because of this, it's sometimes called the universal blood donor type.

Blood group types are based on proteins called antigens that are present on red blood cells. There are major antigens and minor antigens coating the red blood cells. Based on the major antigens, blood groups may be typed as:

  • Type A.
  • Type B.
  • Type AB.
  • Type O.

Blood also is grouped by Rh factor. If your blood has the Rh factor, you're Rh positive. If your blood lacks the Rh factor, you're Rh negative.

It's best if people receive donated blood that works with their type and Rh factor. Even if the types match, small samples from the person getting the blood and the donated blood are mixed to make sure that they're OK together. This process is called crossmatching.

Anyone might get type O red blood cells in an emergency. This is most likely to happen for people who might die without the blood or if there is a shortage of the matching blood type.

With

Rajiv K. Pruthi, M.B.B.S.

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Jan. 25, 2025 See more Expert Answers

See also

  1. Amniotic fluid embolism
  2. Anemia
  3. Aplastic anemia
  4. Blood transfusion
  5. Dengue fever
  6. Esophageal varices
  7. Hemolytic uremic syndrome (HUS)
  8. Hemophilia
  9. Infant jaundice
  10. Myelodysplastic syndromes
  11. Myelofibrosis
  12. Myelofibrosis
  13. Parvovirus infection
  14. Peritonitis
  15. Placenta previa
  16. Premature birth
  17. Radiation sickness
  18. Ruptured spleen
  19. Sickle cell anemia
  20. Thalassemia
  21. Thrombocytopenia