Patient education: Blood donation (giving blood) (The Basics)

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What is blood donation? — Blood donation is the medical term for when a person gives (donates) blood. A person who donates blood is called a blood donor. In the United States, people do not get paid for giving blood. People who give blood do it because they want to. The amount of blood removed during a donation is called a "unit."

When a person gives blood, their blood goes to a "blood bank" or specialized laboratory. There it is tested, made ready for use, and stored until it is needed. Hospitals can get blood from a blood bank to give to patients who need it. When a person gets donated blood, it is called a "blood transfusion."

Who might need donated blood? — People might need donated blood if they:

●Lose a lot of blood in an accident or during surgery

●Have a medical condition that affects their blood

Some people have their own blood drawn and stored if they are planning to have surgery soon. That way, if they need blood during surgery, they can get their own blood.

Who can give blood? — People can give blood at age 17 or older. (Some US states let people give blood at age 16.)

People who want to give blood also need to:

●Be healthy

●Not be taking certain medicines

●Not have been exposed to certain infections

This is important to make sure that the person getting the blood won't get an infection from the donated blood.

Some people want to give blood because they know their blood will be tested, and they want to know if they have certain infections, such as HIV. People should not give blood as a way to get tested for HIV or other illnesses. Doing this could cause the person who receives the blood to get an infection.

To check that you meet all of the conditions for giving blood, a doctor, nurse, or trained staff person will ask you questions and make sure you are healthy enough to donate.

Giving blood during the COVID-19 pandemic — COVID-19 stands for "coronavirus disease 2019." It is caused by a virus called SARS-CoV-2. The virus first appeared in late 2019 and has since spread throughout the world.

During the COVID-19 pandemic, it is very important to avoid contact with people who could get or spread the virus. But because of this, fewer people are giving blood. Doctors are worried that in some parts of the world and the United States, there is not enough blood for people who need it.

If you are healthy and able to give blood, this is a really important time to do it. If you were sick with COVID-19 and recovered, you can donate blood. People who have had COVID-19 can also donate plasma that might help other people. (Plasma is the liquid part of blood.)

If you have gotten any of the COVID-19 vaccines that do not contain live virus, such as "mRNA" or "adenovirus vector" vaccines, you do not have to wait to donate blood. (With certain other vaccines that do contain live virus, you have to wait 2 weeks before donating.)

You can find information online about where to give blood in your area. During the COVID-19 pandemic, some places where you can normally give blood might be closed, and different places might be holding blood drives. You can check 1 of the following places to learn more:

●Your community blood center

●The American Red Cross (www.redcrossblood.org or 1-800-733-2767)

●AABB (www.aabb.org or 301-907-6977)

●OneBlood (www.oneblood.org

●Versiti (www.versiti.org)

●Vitalant (www.vitalant.org)

If you are sick, do not try to give blood. Donated blood is not tested for the virus that causes COVID-19, and you should not donate blood as a way to get tested. If you are infected with the virus, being around other people puts them at risk of getting sick, too.

What questions will I be asked before I give blood? — A staff person will ask you questions about:

●Medical conditions you have or had, including past surgeries

●Medicines you are taking – Some medicines can be dangerous for the person who receives the blood.

●Any recent vaccines that you have gotten

●Whether you have been exposed to certain infections, like malaria or hepatitis

●How you feel that day – You can't give blood if you don't feel well or have a fever.

●Countries you have lived in or traveled to

●Sex partners you have had – Some people have a higher risk of passing on certain infections.

●Any tattoos or body piercings you have

●Any drug use

●Your weight – People who weigh less than 110 pounds (50 kilograms) are usually not allowed to give full units of blood.

●Your last blood donation – People need to wait a certain amount of time before they can give blood again.

What else will happen before I give blood? — The staff person will check your temperature, blood pressure, and pulse (heartbeat).

They will take a small amount of blood from your fingertip to make sure there is enough hemoglobin in your blood. (Hemoglobin helps red blood cells carry oxygen to all parts of the body.) When there is too little hemoglobin in the blood, this is called "anemia." People with anemia might feel fine or they might feel tired or weak. If your hemoglobin is too low, you won't be able to give blood, and you might need treatment. This test will not be able to tell if you have low iron, which is a common cause of anemia.

What happens when I give blood? — You will sit or lie back in a comfortable chair. The staff person will put a needle in your arm. The needle will stay in place while blood is collected from your arm. Giving blood takes about 15 minutes or less.

After you give blood, another staff person will give you some snacks and drinks. They will also watch you for a short time to make sure that you don't have any side effects.

Before you leave, the staff person will give you a phone number to call in case you have any problems or questions. You should call this number if you wish to correct any answers to the questions about medicines, medical history, or risks for infection. You should also call if you remember something you did not think of or did not feel comfortable sharing at the time.

What side effects can I have from giving blood? — The most common side effects include:

●Getting a bruise or feeling sore where the needle went in the skin

●Feeling tired afterward

Some people can feel faint or pass out. This is more likely to happen if it is your first time giving blood or if you are young or your weight is low. To help prevent feeling faint or passing out, drink a big bottle of water before you give blood.

After you give blood, your body will make new blood to replace it. This takes a little while. Most people need to wait at least 8 weeks before they are allowed to donate blood again. Some people take extra iron to help them make more blood. If you are a teenager, were recently pregnant, have monthly periods, or donate blood a few times a year, it might be a good idea to take iron as part of a daily multivitamin. But you should talk with your doctor before trying this, because some people have high iron levels and should not take extra iron.

Will my donated blood be tested for problems? — Your blood will be tested only for some problems. All donated blood is tested for certain viruses. Some of these include HIV, hepatitis B, hepatitis C, and West Nile virus. Blood is not tested for the virus that causes COVID-19. That's because most viruses that affect the lungs are not spread through blood.

Blood is also tested for the bacteria that cause syphilis.

If tests of your blood show you might have any of these infections, the blood bank will let you know. They will also safely throw out your blood. However, it is very important not to give blood as a way to get tested for these infections. Doing this could put another person at risk, and it might not be the best test for your situation.

Donated blood is not tested for other things like iron levels, cancer, diabetes, or cholesterol.

What if I get sick after I give blood? — If you get sick within a few days of giving blood, call the number the staff person gave you. Depending on your symptoms, the blood bank might throw out your blood so it doesn't infect anyone else.