One study cited by the National Institutes of Health found only 1.2 percent of blood donors experienced any kind of adverse reaction from giving blood. The most common side effects from giving blood are relatively mild:
Lightheadedness upon standing is common. Donors are encouraged to rest for at least 15 minutes after the procedure while drinking water and eating a small snack. Some donors find they become nauseous after the procedure, but this should subside quickly.
Pain and some bruising around the injection site is common. Pain should be mild, but it is normal for bruising to persist for several days.
For a few days afterward, the loss of blood may induce dizziness or feelings of weakness when performing strenuous activity. Donors are advised to avoid physical exertion for 24 hours after the procedure, and to be cautious when exercising for the following week.
Very rarely, blood donors may vomit or faint immediately after the procedure. This is generally benign and will resolve itself within hours. Donors should seek medical attention if they experience significant pain or tingling in their arm and around the injection site, or if bruising does not subside within a week. If a donor shows signs of a cold or flu in the days following the procedure, they should call the blood center since this may make the blood sample unsafe to use.
Do blood donors get paid for their donation?
By definition, blood donation is voluntary and done without compensation. Some blood banks do offer cash or other rewards for giving blood. Whether donors are paid or not, blood banks typically serve as intermediaries between blood sources and hospitals. Even voluntarily donated blood is usually tested, separated and sold to medical services for use in blood transfusions and other procedures.
Is it safe to give blood?
Blood donations are considered safe when performed by trained professionals who follow all the necessary procedures. In healthy donors, side effects are generally mild (see below), and serious complications are rare.
Are there restrictions on who can donate blood?
Different organizations have their own restrictions on who is eligible to give blood. The most common requirements stipulate donors must be old enough to give legal consent (17 in most states) and should be in good physical health. Most organizations prohibit donations from people with diseases that can be transmitted through blood, such as HIV and hepatitis. Beyond that, organizations may prevent donations from people who have traveled to or lived in certain countries where there is a greater risk of disease.
There might be additional restrictions in place as eligibility for blood donation is at the sole discretion of the organization collecting it.
How often can someone donate blood?
Blood centers typically allow eligible donors to undergo a whole blood donation once every 16 weeks (56 days). Donations through apheresis are allowed every seven days, up to 24 times per year.