Risks & Complications

The Risks and Complications of Blood Transfusion

Often patients who have received a blood transfusion experience no complications or problems. However, minor to severe problems do occasional occur. Some of the most common complications include:

Allergic Reactions

Some people have allergic reactions to blood received during a transfusion, even when given the right blood type. In these cases symptoms include hives and itching. Like most allergic reactions, this can be treated with antihistamines. However, if the reaction becomes serious, a doctor should be consulted.


Developing a fever after a transfusion is not serious. A fever is your body’s response to the white blood cells in the transfused blood. However, it can be a sign of a serious reaction if the patient is also experiencing nausea or chest pain. Patients should consult their doctors if other symptoms or side effects are present.

Acute Immune Hemolytic Reaction

An acute immune hemolytic reaction is a very serious, but rare, reaction caused by a patient’s body attacking the transfused red blood cells. The attack triggers a release of a substance that damages the kidneys. This is often the case when the donor blood is not a proper match with the patient’s blood type. Symptoms include nausea, fever, chills, chest and lower back pain, and dark urine.

Blood-borne Infections

All donated blood is screened and tested for potential viruses, bacteria, and parasites. However, occasionally these agents can still infect a transfusion patient after the procedure.

The risk of catching a virus or any other blood-borne infection from a blood transfusion is very low.

  • HIV. All donated blood is thoroughly tested for HIV. There is a 1 in 2 million chance that donated blood will not only carry HIV but also infect a transfusion recipient.
  • Hepatitis B and C. The odds of catching hepatitis B from donated blood is about 1 in 300,000. While the risk with hepatitis C is 1 in 1.5 million.
  • West Nile Virus. The risk of catching West Nile Virus from a blood transfusion is approximately 1 in 350,000.

Learn More About Blood Transfusions