How to Prepare for Bloodwork
A step-by-step guide for anyone who is new to getting bloodwork done, or needs a refresher.
So you’re checking out at the doctor’s office and the assistant hands you a paper that includes your “lab order,” or maybe it’s all electronic and your doctor just tells you to “get your blood drawn at your earliest convenience.” If you haven’t had your blood drawn since you were a kid, or maybe you’ve only ever had it done for something like cholesterol, but suddenly you’re figuring out some symptoms of chronic illness, this all might feel new and overwhelming. This guide will help you figure out exactly what to do.
Warning: if you’re especially squeamish, this post might not be for you! We do go through the actual process of getting your blood drawn. Skip step 7 if you don’t want the visual (or skip the whole article completely if you can’t even stand the word “bl**d.” I get it.)
Step 1: Figure out where you’re getting your blood drawn
The easiest place to start is by going to whichever lab your doctor recommended. Some doctors’ offices have labs right next door, or if you see your doctor in a hospital/medical system, they likely have a lab in the building (or one of their other buildings).
If that’s a viable option, there can be an actual advantage to doing this! If your doctor is already in a specific electronic system, it means your labs will also be a part of that electronic system - it just makes it easier to access your own records and communicate with your doctor about your results.
But you don’t necessarily have to use your doctor’s lab, especially if it’s inconvenient for you. (For example, I saw a rheumatologist two hours away from me for 6 years, but I’d of course get my blood drawn closer to home/outside of that doctor’s medical system.)
You can take your order to an independent laboratory like Quest Diagnostics or Labcorp, or a different medical system nearer to you. They’ll just end up faxing your results to your doctor instead of an easy electronic upload. Just make sure you have a physical copy of your lab order that you bring with you, or if your doctor has already transmitted the order via email/fax, you won’t need to (but double check!)
Also, most labs that are part of hospital/medical systems accept walk-ins, but not all, and independent labs like Quest or Labcorp usually need appointments. Make sure you have an appointment if you need one, or choose a lab that accepts walk-ins.
Before choosing a lab, check in on these three things:
Does this location accept your order/perform the specific tests you need to have done?
Is it in-network with your health insurance? (You can see which providers a lab accepts on their website.)
Do you need an appointment or are walk-ins welcome?
If this all feels too confusing, just give your doctor a call. They’ve answered this a million times, it’s no big deal :)
Step 2: Find out if you need to do anything special
Take a look at your lab order, or accompanying instructions from your doctor if you have them, to see if any of your blood tests require any kind of special prep.
The most common is fasting. But remember: not all blood work requires fasting! A lot of tests don’t require anything special at all, while others might require like a 12-hour (basically overnight) fast, like for a lipid panel, and some tests require you to get tested at a particular time of day, like for certain endocrine tests.
Some other tests can involve pausing meds or supplements for a couple of days to get accurate reads on certain levels. This should all be communicated to you ahead of time.
If you don’t have any instructions and it’s your first time getting these tests done, it’s totally fine to message your doctor these questions:
Do I need to fast?
Does this test need to be done at a particular time of day?
Should I take my meds as usual?
Are there any vitamins or supplements I need to avoid beforehand?
Step 3: If you were told to fast, follow the instructions to a T
If your tests do require fasting, don’t cut corners! It will affect your results. Usually this means avoiding coffee, juice, soda, flavored water, and other beverages, but sticking to plain water is totally fine.
This is one of the only times I’m not going to recommend adding electrolytes, either, since electrolytes are going to add sodium to your bloodstream (usually a good thing, because sodium needs replenishing, but it’s important for doctors to get an accurate picture of what’s happening in your body in order to treat you properly). Drink them after you get your blood drawn to replace blood volume!
Getting your blood drawn in the morning is often the most convenient for fasting labs, since you can just stop eating after dinner and then wait to have breakfast until after your labs (unless it’s a 24 hour fast or some other specific instructions).
Also: if you accidentally eat something or drink something other than water, it’s important to let the lab know. They’ll be able to let you know if you can still move forward with the test or not. If you don’t say anything, it’s going to be pretty obvious from your lab work whether or not you fasted properly.
Step 4: Drink water!
Like I said in the last step, water is usually fine to drink before a blood draw (unless you have specific instructions to limit fluids). More than that, water can actually really help the whole blood drawing process run smoother because it helps keep more fluid in your veins, which in turn makes them easier for a phlebotomist to access.
That doesn’t mean you need to chug a gallon of water before your appointment, just try to stay hydrated. But remember, if you have specific hydration instructions from your doctor, those absolutely trump any of this advice!
Step 5: Bring the boring stuff with you
Depending on where you’re getting your blood drawn, a lab might need:
Photo ID
Your insurance card
Your lab order (if it’s a paper copy)
A form of payment (if it’s not just getting billed to insurance)
So make sure you have those one you, or you check in ahead of time to confirm what you do/don’t need.
Also, kind of boring but maybe less boring, make sure you’re wearing something comfortable and relatively easy for the phlebotomist to access your veins (a t-shirt or a tank top is great, and if it’s chilly, wear a sweatshirt, sweater, or a jacket over it that’s easy to remove).
And, if you’re doing a walk-in, sometimes you’ll have to wait a bit in the lobby before your name is called. I like to bring a book, or at least headphones so I can listen to music while I’m waiting.
Step 6: Tell the person drawing your blood any relevant info
If you’re scared of needles, if you tend to faint during blood draws, if people have a hard time finding your veins, if blood makes you queasy, anything like that, a phlebotomist can help make you comfortable. There are different methods to drawing blood that can be more comfortable for people, or faster, or better for people with smaller veins, and whoever is taking care of you that day can also make sure you have a snack right after if your blood sugar/blood pressure seems low, etc. I don’t know how many times a phlebotomist has asked me to describe in detail the most mundane things in my life to distract me from the actual blood draw itself! It’s honestly so helpful!
Just so you know: you absolutely don’t have to watch! You don’t have to be brave! You’re already brave for making this happen.
Step 7: Here’s what actually happens during a blood draw
Because sometimes you just want to know exactly what to expect, I’m going to break it down as simply as possible.
After you check in, you’ll be waiting in a lobby or waiting room for the lab. Then the phlebotomist will call you back and ask for any lab orders that might be in your hand. They’ll lead you to a chair, and this will either be in a room with other blood draw chairs or your own individual room, depending on the facility.
When you sit down, they’ll probably look over your labs and get things prepped: the tube(s) they need to fill with blood for testing, and all of their blood draw materials. They might ask you which arm you prefer for the blood draw, but not always, and this is also a good opportunity to let them know about any relevant information.
Once you’ve both settled on an arm, they’ll put a stretchy band called a tourniquet around your upper arm. This makes the veins below easier to see and feel. From there, your phlebotomist will be looking at your veins and will choose one that seems like it will be good for a blood draw. This is usually around the inside of your elbow, but sometimes it’s a bit lower on your forearm or on the back of your hand. They’ll clean the skin with antiseptic and then insert a small needle into the vein and collect your blood into one or more tubes. You’ll probably feel a quick pinch when the needle goes in, and it can be a very strange sensation knowing there’s a needle in there, but your phlebotomist is holding everything in place so it’s not moving around, won’t tug, won’t push further in, or come out unexpectedly.
If your doctor ordered a lot of tests, you may notice several tubes are being filled, but don’t worry, it’s all coming from one needle. The tubes can get changed out but the needle stays in place. At some point during the blood draw, the phlebotomist will also undo the tourniquet.
Once all of the blood is collected, they’ll put gauze on the spot where the needle is, remove the needle quickly (this usually doesn’t feel like anything, but for some it can be another slight pinch), keep pressure on the spot where the needle was, and place a bit of tape or wrap the area with a bandage.
That’s it! I usually forget I have my bandage on for a couple of hours, but you can remove it even just a few minutes after you leave the lab.
Step 8: Pause before leaving the lab
If you feel totally normal after your blood draw, feel free to just go about your day as normal. Drink some water, though. A relatively small amount of blood left your body, hydrating with electrolytes can be especially helpful to regain a sense of normalcy after a blood draw.
You’ll probably feel a little tenderness in the area, and maybe some bruising, but it’ll resolve on its own after a few days.
If you were fasting, definitely eat something! I like to bring a snack with me to eat right after because I tend to get a little shaky, nauseated, and lightheaded after a blood draw. Take a beat, no one is kicking you out of the waiting room. You can sit still, eat, hydrate, and do what you need to do for as long as you need before leaving.
If you feel really dizzy after the blood draw, tell the staff at the lab. They can monitor you, give you snacks, and give you a comfier place to sit or lie down until you feel better.
Your very exciting, very glamorous bloodwork checklist:
Confirm where you’re getting your blood drawn, and whether you need an appointment
Make sure the lab accepts your order and is in-network with your insurance
Check whether you need to fast or follow any other instructions
Check whether the test needs to be done at a specific time of day
Confirm whether you should take your meds and supplements normally
Drink some plain water before your blood draw, unless told otherwise
Bring your photo ID and insurance card
Bring your lab order if you have a physical copy
Wear something with easy arm access
Bring a book, headphones, or another kind of entertainment for the waiting room
Pack a snack + electrolytes for afterward
Tell the phlebotomist if you’re nervous, prone to fainting or dizziness, or your veins are hard to find
I hope this guide helps you waltz into your next bloodwork appointment with sooo much confidence!