A blood transfusion provides blood or blood components if you’ve lost blood due to an injury, during surgery or have certain medical conditions that affect blood or its components. The blood typically comes from donors. Blood banks and healthcare providers ensure transfusions are a safe, low risk treatment.
A blood transfusion is a common procedure in which donated blood or blood components are given to you through an intravenous line (IV). A blood transfusion is given to replace blood and blood components that may be too low.
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A blood transfusion can save your life. You may need a blood transfusion if you've lost blood from an injury or during surgery, or if you have certain medical conditions including:
In addition to whole blood, a transfusion can provide certain blood components, or parts. These components include:
Typically, the blood comes from an anonymous person who has donated it for use as hospitals see fit. A blood bank holds the blood until needed for a transfusion.
In some cases, though, people donate blood to directly benefit a friend or loved one. You may also have the chance to bank your own blood for a scheduled surgery.
The donated blood or blood components are stored in special medical bags until they are needed. Your healthcare provider connects the needed bag of blood to an intravenous line made of tubing. A needle at the end of the tubing is inserted into one of your veins and the blood or blood components begins to be delivered into your circulatory system.
Before your transfusion, your nurse will:
During your transfusion, your nurse will:
How long a blood transfusion takes depends on many factors, including how much blood and/or blood component you need. Most transfusions take between one and three hours. Talk to your healthcare provider for more specifics about your needs.
The healthcare industry work hard to ensure the safety of blood used in transfusions. Blood banks ask potential donors questions about their health, behavior and travel history. Only the people who pass the blood donor requirements can donate blood. Donated blood is tested according to national guidelines. If there is any question that the blood is not safe, it is thrown away.
Even with these precautions, there’s a small chance something will go undetected in the screening process. However, the odds of this happening are very small. For example, your chances of getting certain diseases from a transfusion are:
You’re more likely to get struck by lightning than to get a disease from a transfusion. The precautions healthcare workers take have helped make transfusions very safe.
People can react in various ways to blood transfusions. Reactions people experience may include:
Most people don’t have any of these reactions. When they do happen, they often feel like allergies. If you experience unusual symptoms during a transfusion, tell your healthcare provider. Stopping the transfusion or getting certain medications can provide relief.
Blood is important. If you don’t have enough blood or one of the components of blood, you could face a life-threatening situation. Blood and the components of blood benefit the body in these ways:
After your transfusion, your healthcare provider will recommend that you rest for 24 to 48 hours. You’ll also need to call and schedule a follow-up visit with your healthcare provider.
Reactions to a blood transfusion can happen at unexpected times. You can have a reaction during the transfusion, a day afterward or up to several months later. Call your healthcare provider right away (or your nurse if you are still in the hospital) if you experience:
Alternatives to blood transfusions exist but may not work in all situations. Medications can help your body produce blood. But if you’ve lost too much blood or your life is in danger, you’ll likely need a transfusion. The alternatives won’t help quickly enough.
You can refuse a transfusion, but you should know the risks and consequences. You’ll need to discuss this option with your healthcare provider. If you choose to refuse the transfusion, you could face permanent disability or loss of life.
A note from Cleveland Clinic
Blood transfusions may worry people or make them feel anxious. But healthcare providers work hard to ensure the safety of these treatments. They take steps to protect you -- from screening donors to making sure to use the right blood. Transfusions work well when people need them. If you’re unsure about receiving a transfusion, talk to your healthcare provider.
Last reviewed by a Cleveland Clinic medical professional on 10/29/2020.
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