FAQ: Donating Blood

Can blood be donated elsewhere for my use at UCSF?

You may be able to donate blood at your community blood bank for your use at UCSF. However, extra time and potential processing and transfer charges by the blood bank performing the blood drawing are necessary. Consult with your local blood bank for their policies and guidelines. You can confirm receipt of blood drawn elsewhere and transferred to UCSF for your use by calling the Blood Availability Line, (888)226-8806.

Can blood be transfused immediately after donation?

No, the donation needs to be processed and tested. This takes three working days from the date of donation.

How long does it take to donate?

The blood donation process takes 30 minutes once the process begins. The actual blood donation takes five to 10 minutes. Platelet donation takes two hours, once the process begins.

Will donating hurt?

There is very little discomfort in donating. Try our pinch test to experience the sensation similar to how a blood donation feels:

  • Bend your elbow slightly.
  • Grab a 1-inch bit of skin on the inside of the bend.
  • Pinch it lightly between your thumb and forefinger.

Will I feel dizzy?

You probably will not. Usually, precautions are taken before, during, and after your donation to ensure your safety. You will be monitored throughout the donation process for any signs of dizziness or light-headedness. All donors are asked to remain seated after their donation to rest and have some refreshments.

Should I eat before donating?

Yes, a low-fat meal taken within four hours of donating is recommended. Refreshments are also available both prior to and after your donation.

What if I am anemic?

Hemoglobin tests that are given and a blood sample from each prospective donor's finger is taken prior to donation. Anemia is not always a permanent condition, so unless you are under a physician's care for anemia, you will be a suitable donor.

Are diabetics acceptable donors?

Diabetics must meet a certain hematocrit level, are under the supervision of a physician, and have stable blood sugar levels. Diabetics taking insulin or other injections must be using disposable syringes.

Will aspirin affect my blood donation?

The chemical composition of aspirin impairs the ability of platelets, a component of blood that plugs leaks in blood vessels to prevent bleeding, to function properly. Platelet donors must refrain from donating for 72 hours if they have taken any products containing aspirin.

How long does it take my body to replace blood I donated?

The body immediately works on restoring blood that was donated. Fluid stored in the tissues returns to the blood stream. Red blood cell production speeds up. A donor's blood volume is restored within a few hours. Red blood cells replace themselves more slowly, but are restored within the interval between donations.

What is the shelf life of blood?

Blood from a blood relative of the patient has a shelf life of 28 days. A non-blood relative's blood has a shelf life of 35 days.

Why is the shelf life shorter (28 days) with donations from blood relatives, as opposed to non-blood relatives (35 days)?

Donations from blood relatives must be irradiated before use. Irradiation shortens the shelf life by seven days.

Irradiation is done to prevent Graft versus Host Disease (GVHD). GVHD is a disease in which the donor's white blood cells attack or "reject" the patient's tissues because the donor's white blood cells identify the patient's cells as "foreign." Irradiation prevents the white blood cells in the donor's blood donation from attacking the patient's tissues, but leaves the rest of the blood (red blood cells, platelets, plasma, etc.) intact.

What is the shelf life of platelets?

Platelets have a shelf life of five days.

Are there special fees for autologous or designated donations?

Many blood donation centers charge a fee for autologous or designated donations, with payment due at the time of donation. UCSF applies all charges towards the patient's hospital bill.

Patients with questions regarding fees and billing for using a blood donation center should:

  • Query the particular blood donation center regarding their fees and billing policies.
  • Query the patient's insurance carriers regarding their fee coverage.

Are there other donors who have increased risks of HIV or other infections who, as a result, are also excluded from donating blood?

Intravenous drug abusers are excluded from giving blood because they have prevalence rates of HIV, HBV, HCV and HTLV that are much higher than the general population. People who have received transplants of animal tissue or organs are excluded from giving blood because of the still largely unknown risks of transmitting unknown or emerging pathogens harbored by the animal donors. People who have recently traveled to or lived abroad in certain countries may be excluded because they are at risk for transmitting agents such as malaria or variant Creutzfeldt-Jakob Disease (vCJD). People who have engaged in sex in return for money or drugs are also excluded because they are at increased risk for transmitting HIV and other blood-borne infections.

Why are some people, such as heterosexuals with multiple partners, allowed to donate blood despite increased risk for transmitting HIV and hepatitis?

Current scientific data from the U.S. Centers for Disease Control and Prevention (CDC) indicate that, as a group, men who have sex with other men are at a higher risk for transmitting infectious diseases or HIV than are individuals in other risk categories. While statistics indicate a rising infection rate among young heterosexual women, their overall rate of HIV infection remains much lower than in men who have sex with other men. For information on HIV-related statistics and trends, go to CDC's HIV/AIDS Statistics and Surveillance Web page.


Reviewed by health care specialists at UCSF Medical Center.

This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.