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Volunteers donate all blood products used for transfusions performed in the United States to help people who are ill or injured, or who need blood for other reasons. Some volunteers undergo a procedure called apheresis that removes only the red blood cells, plasma, platelets, or certain types of white blood cells. Some people donate stem cells through apheresis for relatives or other people who need blood and bone marrow transplants. A person can also have his or her own blood collected and stored a few weeks before surgery in case it is needed.
Most places require you to be in good health, be at least 16 years old, and weigh at least 110 pounds to donate blood. There is no upper weight limit. You cannot donate blood if you are pregnant or have certain conditions, such as HIV or sickle cell disease. If you have sickle cell trait, you may donate platelets, but you should not donate whole blood as it will interfere with later steps involved in handling the donated blood. You may need to wait before you can donate if, among other reasons, you have anemia, are taking antibiotics, have a cold or the flu, or received a blood transfusion within the past year.
Blood donations can occur at a blood bank, special blood donation center, mobile facilities, or a hospital. Sometimes blood donations occur during special events called blood drives. The time it takes to donate blood from start to finish varies based on the type of blood donation; for example, it takes about 1 hour to complete a plasma or whole blood donation and about 2 to 3 hours for a platelet donation obtained by apheresis
All donated blood products are carefully tested and then stored or shipped so they are ready for patients who need a blood transfusion. You can donate whole blood as often as every 8 weeks. Or, certain donors can undergo red blood cell apheresis to donate two units of red blood cells, which is twice as many as in whole blood donation, every 16 weeks. At the NIH Blood Bank, men can donate AB plasma and men and women can donate platelets by apheresis every 4 weeks.
Most healthy adults can donate blood without experiencing any side effects. Some people experience dizziness or nausea after donating blood. To help prevent these complications, you may be asked to sit for 15 minutes after donating blood. You may also be given something to eat or drink during this time. Additionally, because donating whole blood or red blood cells removes iron from the body, these donors need to make sure they get enough iron from food or supplements.
Visit Blood Transfusion and Donation for more information about this topic.
The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discovery to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote safe blood donation and transfusion. Learn about current and future NHLBI efforts to improve health through research and scientific discovery.
Learn about the following ways the NHLBI continues to translate current research to improve blood donation practices and ensure the adequacy and safety of the Nation’s blood supply. Research on this topic is part of the NHLBI’s broader commitment to advancing blood disorders and blood safety scientific discovery.
Learn about some of the pioneering research contributions we have made over the years that have improved blood donation.
In support of our mission, we are committed to advancing blood donation research in part through the following ways.
Learn about exciting research areas the NHLBI is exploring to improve blood donation and the safety of donated blood products.
We lead or sponsor many studies relevant to blood donation. See if you or someone you know is eligible to participate in our clinical trials or observational studies.
To learn more about clinical trials at the NIH Clinical Center or to talk to someone about a study that might fit your needs, call the Office of Patient Recruitment 800-411-1222.
Learn more about participating in a clinical trial.
View all trials from ClinicalTrials.gov.
After reading our Blood Donation Health Topic, you may be interested in additional information found in the following resources.
The National Heart, Lung, and Blood Institute, NIH and the Office of the Assistant Secretary for Health, DHHS will ...