How long does it take to replenish blood after blood test

It’s likely that at some point in your life, you’ll have blood drawn for either a medical test or for donating blood. The process for either procedure is similar and usually much less painful than most people think.

Read on to find out how to prepare for your next blood draw. If you’re a medical professional, we’ll provide a few tips for enhancing blood drawing techniques.

Before you have a blood draw, it’s important to know if you need to follow special instructions before your test.

For example, some tests require that you fast (don’t eat or drink anything) for a certain amount of time. Others don’t require you to fast at all.

If you don’t have any special instructions other than an arrival time, there are still some steps you can take to try to make this process easier:

• Drink plenty of water before your appointment. When you’re hydrated, your blood volume goes up, and your veins are plumper and easier to access.
• Eat a healthy meal before you go. Choosing one with plenty of protein and whole-grain carbohydrates may prevent you from feeling light-headed after giving blood.
• Wear a short-sleeved shirt or layers. This makes accessing your veins easier.
• Stopping taking aspirin at least two days before your blood draw if you’re donating platelets.

You may wish to mention if you have a preferred arm for a person to draw blood from. This could be your nondominant arm or an area where you know a person taking your blood has had success before.

The time it takes for a blood draw usually depends upon the amount of blood needed.

For example, donating blood can take about 10 minutes, while obtaining a small amount of blood for a sample may take just a few minutes.

While the process may vary depending on who is drawing the blood and for what purpose, the person performing the blood draw will follow this general procedure:

• Ask you to expose one arm, and then place a tight elastic band known as a tourniquet around that limb. This makes the veins back up with blood and be easier to identify.
• Identify a vein that appears easy to access, specifically a large, visible vein. They may feel a vein to assess the borders and how large it may be.
• Clean the targeted vein with an alcohol pad or other cleansing method. It’s possible they may have difficulty accessing the vein when they insert the needle. If this is the case, they may need to try another vein.
• Insert a needle successfully into the skin to access the vein. The needle is usually connected to special tubing or a syringe to collect blood.
• Release the tourniquet and remove the needle from the arm, applying gentle pressure with a gauze or bandage to prevent further bleeding. The person drawing blood will likely cover the puncture site with a bandage.

Some blood product types may take longer to donate. This is true for a special type of blood donation known as apheresis. A person donating via this method is providing blood that can be separated into further components, such as platelets or plasma.

While drawing blood is ideally a fast and minimally painful experience, it’s possible that some people will feel very nervous about getting stuck with a needle or seeing their own blood.

Here are some ways to minimize these reactions and stay calm:

• Focus on taking deep, full breaths before getting a blood draw. By focusing on your breathing, you can relieve mental tension and naturally relax your body.
• Take your headphones and listen to music before and during the draw. This allows you to block out an environment that might otherwise make you feel nervous.
• Have the person taking your blood tell you to look away before they bring a needle near your arm.
• Ask if there are devices or methods the person drawing blood can use to minimize discomfort. For example, some facilities will use numbing creams or small lidocaine injections (a local anesthetic) before inserting a needle into the vein. This can help minimize discomfort.
• Use a device like Buzzy, a small vibrating tool that can be placed nearby that helps reduce the discomfort of needle insertion.

The person drawing your blood has likely seen nervous individuals about to have their blood drawn before. Explain your concerns, and they can help walk you through what to expect.

Most blood draws cause minimal side effects. However, it’s possible you could experience some of the following:

• bleeding
• bruising
• lightheadedness (especially after donating blood)
• rash
• skin irritation from tape or adhesive from an applied bandage
• soreness

Most of these will subside with time. If you still experience bleeding from a puncture site, try holding pressure with a clean, dry gauze for at least five minutes. If the site continues to bleed and soak bandages, see a doctor.

You should also see a doctor if you experience a large blood bruise known as a hematoma at the puncture site. A large hematoma can block blood flow to the tissues. However, smaller (less than dime-sized) hematomas will often go away on their own with time.

Even if you’ve had a small amount of blood drawn, there are still steps you can follow to enhance how you feel afterward:

• Keep your bandage on for the recommended amount of time (unless you experience skin irritation at the puncture site). This is usually at least four to six hours after your blood draw. You may need to leave it on longer if you take blood-thinning medications.
• Refrain from doing any vigorous exercise, which could stimulate blood flow and may cause bleeding from the site.
• Eat foods rich in iron, such as leafy green vegetables or iron-fortified cereals. These can help replenish lost iron stores to build your blood supply back up.
• Apply a cloth-covered ice pack to your arm or hand if you have soreness or bruising at the puncture site.
• Snack on energy-boosting foods, such as cheese and crackers and a handful of nuts, or half of a turkey sandwich.

If you do experience any symptoms that you’re worried are out of the ordinary, call your doctor or the location that did your blood draw.

Blood draws and blood donations should be a minimally painless process that has few side effects.

If you’re interested in donating blood, consider contacting your local hospital or the American Red Cross, which can direct you to a blood donation site.

If you do have concerns about side effects or the process itself, share these with the person taking your blood. There are many ways to soothe nerves and make the process smoother overall.