There are millions of people who are helped by donated blood. Blood loss from an accident or illness such as hemophilia, sickle cell disease, anemia or cancer can lead a person to need a blood transfusion. Thankfully, there are banks where people can go and donate their blood to those who need it. Generally, this is a simple, hassle-free experience. However, a few people end up fainting after giving blood.

Why Do You Feel Faint After Giving Blood?

When you give blood, your overall volume of blood will decrease, which will cause a sudden drop in your blood pressure. This drop is why some people feel faint once they have given blood. The decrease in your blood sugar level plays a role as well.

The emotional stress involved when donating can cause the body to react with a fight or flight response. This may drive blood to your muscles, diverting it from the brain, raising the risk of fainting yet again. This emotional component can be from needles, seeing blood, or seeing others donating.

Some factors increase your risk:

• Fatigue
• Not enough sleep
• Giving blood on an empty stomach
• Pain of the needle prick

There are some people who have symptoms before passing out, which is called presyncope. Some of these signs include dizziness, sweating, lightheadedness, nausea, stomach ache, heart palpitations, trouble speaking or confusion. If you feel any of these after donating, please notify the professional right away.

Who Is Most Likely to Faint After Giving Blood?

There are some medical conditions that will leave certain people predisposed to fainting after giving blood. Some examples are heart blockage, panic disorders, anxiety, hypoglycemia, diabetes, irregular heartbeat and dehydration. You should discuss your medical history with the professional at the donation center before giving blood to make sure you can.

What to Do If You Feel Faint After Donating Blood

If you feel faint after you donate, notify the nurse immediately. Be sure to sit down right away, even on the ground. If you can, put your head between your knees for a moment. Lie down if necessary. Stay in a lying down position or sit for half an hour or until you feel better. When you do get up, go slowly. If you feel dizzy again, lie back down. Try the following things to recover.

• Stay hydrated and enjoy a salty snack. Steer clear of caffeine and alcohol.
• Enjoy regular meals.
• Avoid warm showers or rooms.
• Steer clear of moving too fast or exercising rigorously.
• Don’t stand for extended periods of time.
• Be gentle with the arm you donated from. Avoid carrying heavy things.

If you lose consciousness after giving blood, check with your regular doctor afterward. Donating may be advised against.

Tips to Avoid Fainting After Giving Blood

1. Eat Foods Rich in Iron

When you give blood, you remove some of your red blood cells. This will reduce your iron stores which transport oxygen in your blood. In the weeks before you donate, you need to eat an iron-rich diet. Some foods to include are leafy green veggies, fish, poultry, eggs and red meat. Some cereal is also fortified with iron. Be careful to avoid tea during this time, because the tannins can interfere with you absorbing the iron.

2. Increase Your Vitamin C Intake

Eating foods rich in vitamin C can help you absorb iron. Make sure to enjoy a healthy breakfast with cereal and a glass of orange juice on the day you donate. You can also enjoy citrus fruit or dried fruit.

3. Avoid Fats

Eating a high fat meal before you donate will increase the lipids in your blood. If your donated blood is high in lipids, it can’t be tested for infections. These samples will be rejected.

4. Staying Hydrated

When you donate blood, your body fluid levels will decrease. Start your day well hydrated and this will be less of a problem. Drink 16 ounces of water first thing in the morning. Steer clear of carbonated drinks like soda and stick to juice and water. You can get a drink after you donate as well to help you keep from fainting and to start replacing the fluid you lost.

5. Sleep

Be sure to get a good night’s rest before the day you donate. If you are tired, your hormones can be imbalanced and cause issues. If it is your first time of donating, lack of sleep can increase anxiety.

6. Give Your Body Time to Recover

Don’t start rushing around after you donate blood. This can increase your feeling of faintness. It’s best to sit for a few minutes or even lie down if needed. Make sure to enjoy the snack the nurse gives you, which will help restore your blood sugar and prevent shock. For those who tend to have lower blood pressure, a salty snack is preferred.

7. Get Over Your Fear of Needles

Overcoming the fear of needles can help prevent fainting after giving blood.

• Focus on those you may be helping when you donate. Just a single pint of blood can save up to three lives. It is only a pinch, over in seconds and that could help someone for a lifetime.
• Familiarize yourself with the process. When you know what to expect, it is easier to not get scared.
• Distract yourself. Close your eyes, listen to music or talk to the technician.
• If you are nervous, make sure your technicians know. They can help you by letting you know what they are doing and talking to you through the procedure.
• Bring a friend for support. Having another person there with you can help you get through the process.