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. A person can also have his or her own blood collected and stored a few weeks before surgery in case it is needed.
To donate blood, you must be in good health, weigh at least 110 pounds, and be at least 16, 17, or 18 years old, depending on where you live in the United States. You cannot donate blood if you have certain conditions, such as sickle cell disease or hepatitis or if you are pregnant. You may need to wait before you can donate include 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 hospital, blood bank, special blood donation center, or mobile facility. 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 one hour to complete a whole blood donation and close to three hours to complete 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 blood as often as every eight weeks, or up to six times a year. You can donate plasma every four weeks, or up to 12 times a year. You can donate platelets as often as every seven days, or up to 24 times a year.
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, blood donors who give these kinds of donations need to make sure they get enough iron from food or supplements.
Visit Blood Transfusion and Donation for more information about this topic.
The National Heart, Lung, and Blood Institute (NHLBI) leads or sponsors many studies aimed at preventing, diagnosing, and treating heart, lung, blood, and sleep disorders.