Patients who need blood the most, such as people with cancer, heart surgery, and accident victims, benefit when you donate blood. One pint of donated blood can save up to three lives. Blood donations are always needed.
Blood is essential for life. It contains components that transport oxygen throughout the body and also fight infection. There is no man-made substitute for blood. It is only made in the body. Many patients depend on life-saving transfusions for a number of medical conditions, such as surgery and cancer treatments.
A healthy body can regenerate, or make more, blood in about 4 to 6 weeks. Donating one pint is a small amount of the body’s total blood supply. Typically, there are about 10 to 12 pints of blood in a person’s body.
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You must be at least 17 years old in Florida (or at least 16 years old with parental/guardian consent in Ohio and some other states), weigh 110 pounds or more, and be in good health. If you have a cold or the flu on the day you are scheduled to give blood, you should cancel your appointment and reschedule once you are feeling better.
There are some health concerns that can temporarily prevent you from giving blood, such as:
Other health concerns will permanently prevent you from giving blood, such as:
Donating blood is generally simple and quick. It takes a total of about one hour of your time. Although the actual donation time is about 10 minutes, there are some items that need to be taken care of before and after the donation process.
When you arrive to donate blood, you need to show an ID, such as a driver’s license or passport. You then are asked several health questions, including what types of medication you are taking, both prescription and over-the-counter. The questions are personal. It is very important that you read all of the information carefully and answer all of the questions honestly. The answers are kept confidential.
A quick exam also takes place to ensure that you are healthy enough to give blood. A nurse or technician takes your temperature, blood pressure and pulse. The technician also takes a small sample of your blood with a finger stick to make sure your hemoglobin is not low.
During the actual blood donation, you are either lying down or sitting in a chair. First, the area inside of your elbow is cleaned with antiseptic. Next, the technician inserts a needle into a vein in your arm and draws a pint of blood out of your body. It is not usually painful, but you will feel a prick when the needle goes through your skin.
Afterwards, you are given a small snack and something to drink. You are asked to remain seated for about 15 minutes to make sure there are no side effects or problems. You can leave after you have rested and are sent home with instructions to take it easy, drink plenty of water, and avoid strenuous exercise for the next day or so.
Most people describe only feeling the needle pricking the skin as it enters, without other discomfort. Very few donors have other issues during or after donating.
After giving blood, some people may feel a little dizzy or weak. That is why it is important that you rest for several minutes before leaving. It is also best to eat a snack and have a drink of water or juice right after you donate blood.
The donation is tested for blood type and for certain infectious diseases, but you should never donate blood for the purpose of getting tested for infectious diseases, you should see your doctor for that instead. Each pint of donated blood goes through some laboratory tests for infectious diseases before it can be used for patient care. If it does not pass these tests, the blood cannot be used and is safely thrown away. The donor will be notified when this happens.
The blood then goes to the lab where it is tested for blood type and the red blood cells, platelets, and plasma are separated. The blood is usually available for patient use about 1 to 2 days after collection.
Volunteer blood donations will go to patients who need blood the most. Typical recipients are those patients going through:
You can also donate blood for use by a family member or friend who has the same blood type as you. This is called a directed donation.
Sometimes, a healthy person can donate blood prior to a non-emergency surgery. This blood is stored and available for surgery only for the person who donated it. This is especially helpful for patients who are difficult to find blood for because of antibodies. This is called an autologous donation.
Donating blood can save someone’s life. In fact, one pint of your blood can save up to three lives. There is always a need for blood. It is used every hour of every day at hospitals during surgeries and treatment of injuries and chronic illnesses in patients of all ages.
Most donors do not experience discomfort after donating. You may feel lightheaded, tired, or dizzy after giving blood, so you should not plan to do anything strenuous after donating. The place where you donate blood will give you information afterwards on how to care for your bandage and other instructions.
Sterile materials are used and discarded safely after one-time use on the donor. This is for the safety of the person who receives the blood, as well as the safety of the donor, and the staff collecting the blood.
After donating blood, you will be able to return to your regular routine soon. It is best to follow the donation center’s instructions after your donation. It is also important to immediately let the donation center know if you think of health information that you did not inform them of previously, or if you develop other issues such as fever, muscle aches and others, according to their instruction sheet. If you are a regular donor, talk with your doctor about adding multivitamins to your diet to make sure that you are not depleting your iron and other vitamins when giving blood.
Because a healthy body continues to make blood, new red blood cells will replace those that were donated in approximately four to six weeks. It is safe to donate whole blood every 56 days, but may be sooner or longer depending on the type of blood component that is donated.
Last reviewed by a Cleveland Clinic medical professional on 04/05/2019.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy