Blood Donation: Myths, Facts, and Preparation

Published on October 23, 2023 .

Blood bags — Image by Charlie-Helen Robinson via Pexels

A blood transfusion can mean the difference between life and death. You might need a blood transfusion if you have been injured, had surgery and lost a significant amount of blood, or have an illness that depletes blood levels in your body.

If you or someone you love does need a blood transfusion, the blood will likely come from a stranger who decided to share generously before the emergency occurred. Before donating blood, there are several things to consider, such as whether you should donate blood and have the ability to, along with considerations about why you should do it.

Reasons to donate blood

There are several reasons donating blood may be a good idea:

Your blood might save a life, possibly up to three lives. Every two seconds, someone needs a blood transfusion in the United States.
You get a free mini check-up. Before you donate blood, a healthcare worker will check your blood pressure, heart rate, temperature, and hemoglobin level.
Helping others helps you feel better as well. Giving blood can help you feel connected with others; less isolated.
Free snacks. Most donation centers give out snacks to prevent some of the side effects of giving blood, like dizziness and fatigue.

How do I know if I can donate blood?

Most people can donate blood. If you have any questions, call your donation center in advance. But the criteria for donating blood are pretty simple.

You must be:

Generally healthy.
At least 110 pounds.
At least 17 years old (in most states).
Eight weeks past the last time you donated.
Carrying a photo ID.
Able to pass the health history assessment. This is a series of questions to determine if you are at high risk for an infection in your blood.

Blood donation myths

Here are some common myths about blood donation:

Myth	Fact
It will hurt a lot.	When the needle is placed in your arm you will feel a prick; after that, you probably will not feel any more pain during the rest of the procedure.
If you don't have a rare blood type, your blood isn't needed.	All blood types are needed, whether it is considered rare or not.
You can't give blood if you are taking medication.	Some health conditions will exclude you from donating blood, but most medications will not. Keep in mind that you might need to wait for a week after your last dose of certain medications before donating; you can check with the American Red Cross for medication restrictions.
You are too old.	There is no top age limit for giving blood. If you are seventeen (16, with a parent's permission, in some states) or older, you can donate blood if you are healthy and have no other exclusion criteria.
It takes too long.	The whole process takes about one hour. You register, they give you a quick check-up, you donate blood, and they keep an eye on you for a few minutes before they let you go.
You can't give blood if you have a tattoo.	In most states, you can give blood if you have a tattoo, but you need to wait 12 months after you get one before you can donate blood.
You can't give blood if you have high blood pressure.	If your systolic pressure, the top blood pressure number, is not over 180 or less than 100, you can donate blood. Being on blood pressure medications will not exclude you either.

Side effects after giving blood

As with any medical procedure, you are at risk of developing side effects from giving blood. These side effects are usually mild and will resolve with rest, fluids, a snack, and maybe an ice pack.

You may experience some of the following things:

Minor bleeding at the site.
Bruising to the site.
Pain at the site.
Dizziness or lightheadedness.
Fatigue.

How to prepare

Plan on being at the donation center for about an hour.
If you are taking medication, you can check with the American Heart Association to find out if you can give while taking a particular medication. Do not stop any medication without talking to your doctor first.
Get a good night's sleep and eat a good healthy breakfast in the morning before you donate.
Wear a short-sleeved shirt or one with sleeves that are easy to roll up.
Bring your photo ID and a book to read while sitting there.
Drink plenty of fluids before and after donating, and bring extra snacks to eat afterward.

What should I do after I donate blood?

The healthcare workers will watch you for about 15 minutes after the procedure. They will probably give you a snack and some water or juice. Once they have cleared you as safe to leave, you can go.

Follow these tips and tricks to avoid problems with side effects after donating blood.

Keep your bandage on for at least 5 hours. If the site starts to bleed when you remove the bandage, apply pressure, and raise your arm above your head until the bleeding stops.
Drink plenty of water or juice.
Eat food rich in iron, such as turkey, beef, and beans; and foods rich in B-vitamins, such as bananas, potatoes, and leafy greens.
If you start to feel dizzy or lightheaded, lie down and put your feet up if possible.
If you have significant bruising, put an ice pack on the site every few hours for the first 24 hours.
Avoid strenuous activity or heavy lifting for five hours.
Call the blood donation center if you forgot to tell them something important in your health history, you are diagnosed with Covid-19 within 48 hours, or you start having symptoms of an illness (such as a fever) within a few days of giving blood.
Call your doctor if you cannot stop the bleeding; you continue to feel dizzy or fatigued; or your arm becomes tingly, numb, or starts to swell, especially in the presence of a fever.