NIH Blood Bank

After Your Donation

Once You're Done

The NIH Blood Bank asks that you relax in the donor recovery area for at least 15-minutes after giving blood or platelets – we encourage you to enjoy the snacks and hydrate while you wait! Make sure to inform our medical staff if you are experiencing any adverse symptoms at any time before, during, or after your blood or platelet donation.

  • Keep the bandage wrap on for the next 2-3 hours; to avoid a skin rash, clean the area gently with soap and water.
  • Do not do any heavy lifting, vigorous exercise, or work from heights for the rest of the day.
  • If the needle site starts to bleed, apply pressure to the site and raise your arm straight up for about 5-10 minutes or until the bleeding stops.
  • Drink an extra four (8 ounce) glasses of liquids and avoid alcohol over the next 24-hours.
  • If you become dizzy or lightheaded, sit down or lie down immediately; do not resume normal activity until all symptoms have resolved.
  • Contact us if you experience any adverse symptoms requiring medical care when you leave the NIH Blood Bank.

When You Leave You Might Experience

Dizziness / Fainting 
Some donors have lightheadedness and/or nausea after donation and in some cases, faint. Always remember to stop what you are doing and sit or lie down if you start feeling dizzy. Do not attempt to resume normal activity until your symptoms have resolved; abstain from any activity where fainting might lead to injury for 24-hours. Please contact us if symptoms persist for more than 30 minutes and/or for any symptoms requiring medical care.

Bruising or pain at the site of the needle may occur after blood donation as a result of bleeding under the skin. Swelling or discoloration may occur and move up or down the arm, or around to the elbow. The bruise may change colors and take a week or more to heal completely. To treat a bruise, apply a cold pack to the bruised area for 20-minutes at a time, twice a day for the first 24-hrs, and then switch to intermittent, warm, moist heat. If you are experiencing pain you can use over-the-counter pain medications that do NOT contain aspirin.

If you start to experience any tingling or numbness in your fingers or arm; any redness, swelling, or pain where the needle was inserted; or at any time your symptoms have worsened, you may need additional care. Please contact for follow-up.

Maintaining Your Iron Level After Blood Donation

Iron is needed to make new red blood cells. The amount of iron you need depends on many factors, including age, gender, and how often you donate blood or platelets. Frequent blood donors may experience low levels of iron which is lost during donation, resulting in anemia or a low hemoglobin value.

Hemoglobin is a protein in your blood that contains iron and gives blood its red color. Hemoglobin carries oxygen from your lungs to nourish all the tissues in your body. We check your hemoglobin level before every blood donation to ensure you meet the minimum requirements for donation. If your hemoglobin is too low you will be asked not to donate blood until your levels increase:

  • Female blood donors must have a hemoglobin level of at least 12.5 g/dL
  • Male blood donors must have a hemoglobin level of at least 13.0 g/dL.

How Much Iron Is Needed to Replace the Iron Lost In One Whole Blood Donation?

New studies show that lower doses of iron (18-27 mg iron) that are available in multivitamins or over-the-counter (OTC) iron supplements are as effective as higher doses in prescription iron (38-65 mg elemental iron) when taken for 60 days in an effort to replenish the iron lost with blood donation; they are also associated with fewer side effects.

It is recommended that donors take an OTC multivitamin with iron or iron supplement with 18 mg or 27 mg iron (1 tablet a day for 60 days) before their next blood donation. You should discuss blood donation and any supplements that you take with your healthcare provider.

Iron and Your Diet

All blood donors should add foods rich in iron and high in vitamin C to their diet. Such foods include lean meat, seafood, poultry, iron-fortified cereals, beans, lentils, tofu, and fresh spinach.

Plant-based foods such as fruits, vegetables and nuts contain iron and are a part of a nutritious well-balanced diet, but the iron contained in these foods is not absorbed as completely as the iron in meat, fish and poultry. Your body absorbs iron from plant sources better when you eat it with meat and foods that contain vitamin C, like orange juice, citrus fruits, and tomatoes. View additional information on iron in your diet.

Iron Supplements

Frequent blood donors should take a multivitamin with iron in it or an iron supplement to replace the iron lost with blood donation. You are a frequent blood donor if you are:

  • A woman, 18 – 50 years old who donates 2 or more units/year
  • A woman > 50 years old who donates 3 or more units/year
  • A man who donates 3 or more units a year
  • A frequent apheresis donor

What Kinds of Iron Dietary Supplements Are Available?

  • Iron is available in many multivitamin-mineral supplements or in supplements that contain only iron; check the nutrition label for 18-27 mg iron or 38 mg iron
  • Tablets labeled "325 mg ferrous gluconate" usually contain 38 mg of iron, which is also called "elemental iron"; please check the labeling
  • If you experience side effects such as stomach upset, nausea, constipation, or other gastrointestinal symptoms, try taking a lower dose
  • Ferrous gluconate might cause fewer side effects than ferrous sulfate
  • Always follow the directions on the package
  • Keep iron and all medications out of reach of children; accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under age 6
  • For more information about iron supplements, see the NIH Office of Dietary Supplements.

Athletes and Blood Donation

Athletes should wait about 12 hours to resume strenuous exercise after blood donation, depending on how they feel. Blood donation causes fluid loss which the body replaces within 24-hours when you drink extra fluids. As a precaution, do not donate blood on the same day of a competition or strenuous practice. Your body also replaces the red blood cells (the cells that deliver oxygen to muscles and tissues) that are lost during whole blood donation - within about five weeks- depending on nutrition and iron status. Competitive athletes may notice a marginal decrease in exercise tolerance for about one week after whole blood donation.

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This page last updated on 05/24/2024

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