Weed And Donating Blood: All You Need To Know

smoking weed and donating blood

Uh oh. Did you just smoke weed and then remembered that you are planning to give blood within the next few days? 

If you are in a state of asking yourself, “Can you donate blood if you smoke weed?”, then look no further! 

We’ll tackle all the can’s and cant’s when it comes to weed and donating blood!

Can You Donate Blood/Plasma If You Smoke Weed?

The short answer - yes!

So long as you are not cognitively impaired (aka obviously high) when you show up to donate, then you are generally good to go!

The use of cannabis in and of itself does not disqualify anyone from donating blood and/or plasma. 

In fact, according to the American Red Cross, the U.S. Food and Drug Administration (who regulates blood donation eligibility) does not even require that donated blood be tested for THC. 

Granted, every donation facility will have its own testing procedures, but the chances of your blood being tested for THC after you’ve donated is slim to none. 

FAQ’s About Cannabis Use And Donating Blood

Now that you know that you can donate blood and plasma as a cannabis user (so long as you don’t show up high!), let’s dig into all those frequently asked questions about blood donation and weed. 

Do They Report Cannabis Use If I Donate Blood? 

Okay, so you are in a position where you would like to keep your smoking habits on the down low. Does that mean that if you donate blood, you are going to sound the alarm on yourself?

Since the FDA does not require blood and plasma to be tested for THC, most blood donation facilities don’t see a need to test for it. 

The American Red Cross even states that itdoes not test for THC.  

If you want to make sure that your facility isn’t going to test your blood for THC, simply ask them for a list of what they test blood for. Having that information handy before making your donation will help put your mind at ease!

How Long Does Cannabis Stay In Your System? 

how long does cannabis stay in the system

Curious how long weed will last in your system after you smoke or take an edible? Well, that actually depends mostly on what testing method is being used and how active of a user you are. 

Blood Test

THC levels can be detected in your bloodstream anywhere from one to seven days, depending on how active a user you are. 

Urine Test

A urine test can detect THC within one day and for up to more than a month. Factors such as how heavy a user you are and how quickly your body metabolizes the cannabis play a key role in urine tests. 

Hair Follicle Test

Hair tests are capable of testing back the longest, with these tests able to detect THC for up to 90 days. 

Saliva Test 

A saliva test will be able to detect THC typically for 24 to 30 hours, depending on how heavy of a cannabis user you are. 

Now, how long weed stays in your system is a much different topic than how long you will feel the effects of THC in your body. 

If you’re smoking, you’ll feel the impacts of weed once you take your hit. Depending on how much you smoke, you’ll most likely be riding out that high for a couple of hours or more. 

When you eat edibles, the high takes anywhere from 45 minutes to an hour to kick in. You’ll also find yourself riding it out for three to four hours or more, depending on how high of a dose you take. 

Can I Donate While High? 

The American Red Cross specifically states that “potential donors cannot give if their use of cannabis impairs their memory or comprehension.” 

They further request that people “do not present to donate if your use of cannabis is impairing your memory or comprehension.”

So what does that mean? 

If you show up to donate blood or plasma and the facility suspects that you are high, they are going to ask that you come back to donate at another time. 

Can I Smoke After Blood Donation?

It’s not a good idea to smoke weed immediately after donating blood. 

When you donate, you’re giving up 1 pint of your body’s blood. A typical adult has anywhere from 8 to 12 pints of blood, so 1 pint is a pretty decent percentage! 

Because of this, donating blood can lead you to feel a bit dizzy, lightheaded, tired or even nauseous. If you light up (or even take an edible) right after you donate, you could risk making these symptoms worse. 

It’s best to wait a few hours to a day before getting high again after donating blood to help your body fully recover from the short-term side effects of donating. 

Do The Guidelines Differ If I’m Donating Plasma Versus Blood?

If you use cannabis, then the American Red Cross guidelines are the same whether you are donating blood or donating plasma. 

What About If I Use Synthetic Cannabis Instead Of Regular Weed?

If you use synthetic cannabis, then things are slightly different. 

Certain synthetic weed options run the risk of containing anticoagulants that can actually contaminate plasma. Because of this, facilities are more cautious when it comes to donations. 

The American Red Cross says that “The FDA does not have universal guidelines regarding synthetic marijuana (aka synthetic cannabinoid, K2 or Spice) and leaves decisions about the acceptability of donations from these users up to local blood centers.”

Your best bet in this scenario is to contact your donation facility directly and see if they’ll accept your donation before you schedule an appointment. 

General Requirements For Donating Blood 

Now that you know the can’s and can’t’s of donating blood if you smoke weed, let’s chat about the process of donating blood!

There are a few general requirements to know before you go to donate. 

Wait Period

First, you’ll need to wait at least 56 days from your last blood donation before you can go donate again. 

The reason for this is that when you donate blood (or whole blood), you are losing plasma, platelets and red blood cells from your body. 

Your body will replace your plasma pretty quickly (usually within 24 hours). 

Your red blood cells, on the other hand, take a bit longer. It usually takes anywhere from four to six weeks for your body to replace your red blood cells when you donate blood. 

Because of this, you are required to wait 56 days before your next donation. 


The minimum age to donate blood is 16 years of age. 

This may vary from state to state, so make sure to confirm at your local donation facility. 


In order to donate blood, you must weigh at least 110 lbs. 

Since your blood volume is proportional to your body weight, it’s important to make sure you have enough blood in your body to tolerate the needed amount of 1 pint to be removed for donation. 


Lastly, you need to be in good health and feeling well before you go to donate!

When you go to donate, the facility will check your vital signs first to make sure you are in a good enough physical state to donate. 

General Requirements For Donating Plasma

If you’re looking to donate plasma instead of blood, the general requirements are going to be different than if you are donating whole blood. 

Wait Period

Since you are just donating your plasma and not your whole blood, you don’t have to wait as long between donations to go back. 

For plasma, you’ll need to wait at least 28 days from your last donation before you can donate again. 


The age requirement for donating plasma is also different than when you donate whole blood. 

The minimum age to donate plasma is 17 years of age. 

This also may vary from state to state, so make sure to confirm at your local donation facility. 


The weight requirement is the same whether you are donating blood or plasma, coming in at a minimum weight of 110 lbs. 


And just like blood donations, you need to be in good health and feeling well before you go to donate plasma.

Blood Type

One major difference when it comes to donating plasma versus donating whole blood is that for plasma, you need to be a specific blood type. 

Plasma donations are only available for people with type AB blood. 

Health Benefits Of Donating Blood

Not only is donating blood good for others, but it’s also good for you! 

Donating blood on a regular basis has been connected to people having lower cardiovascular risks and lower blood pressure. 

That means that donating blood is good for your heart!

After you donate, your body takes time to replenish the blood that you lost. So, regularly donating sets your body up to be consistently creating new blood to pump through your veins. 

It’s basically a blood detox!

While you’re riding that health kick of keeping fresh blood flowing through your body, check-in and make sure that you are maintaining ahealthy high habit as well!

If you like to smoke your green instead of eating edibles, make sure you are using filters and othermethods to minimizethe negative impacts on your body of the smoke, tar, and resin. 

Things To Know Before You Go

Here are a few tips and tricks to help you have the best possible donation experience!

Book Your Appointment Ahead Of Time 

It’s common for donation facilities to require you to have a scheduled appointment prior to arriving. 

Do some research with your local facility and book your appointment ahead of time when applicable. This will save you from showing up when no slots are available!

While you’re getting your appointment booked, it’s always good to run a quick check of the facility requirements to make sure everything is in line with what you were expecting. 

Before And After You Donate

In the day leading up to your donation, you’ll want to make sure you do the following to help aid you in having a favorable donation experience!

Drink Lots Of Fluid

Hydrate, hydrate, hydrate! 

You’ll be losing 1 pint of blood when you donate, so you’ll want to make sure you are replenishing your body’s liquids both before and after you donate. 

This will also help you mitigate the chances of feeling light-headed and dizzy after donating. 

Eat Iron-Rich Food

Donating blood depletes the amount of iron in your body, making you feel tired and weak. 

Eating iron-rich foods before and after you donate can help you mitigate this side effect of blood donation.

Don’t Get High

Remember, if you show up obviously blazed, the donation facility will ask you to come back another time. 

For this reason, it’s good you don’t get high in the hours leading up to your donation appointment. 

And since your body will be missing its long-lost pint of blood, you should take a break from your bud for a few hours after you donate. 

Take Some Time To Chill

It’s best to leave yourself some time just to hang out and chill after you donate while your body adjusts to its new levels. 

So, hunker down with a good movie, book, or other chill activity while you wait out the side effects of your donation. 

Why One Wouldn’t Be Able To Donate Blood 

While blood donation centers are always in need of donations, there are a number of reasons why people would not be eligible to donate. 

Here’s a quick list to see if any of these apply to you. 

Drugs Or Alcohol In Your System

Currently high or drunk? Then save your donation for another time!

Facilities won’t accept you for a blood donation if you are noticeably impaired. 

Also, if you use synthetic cannabis, K2, or Spice, then chances are high that the facility won’t accept your blood. 

This also includes steroids. The use of steroids will make you ineligible to donate. 

Recent Tattoo Or Piercing

If you’ve been purposefully punctured with a needle within the last year, then you are not eligible to donate blood. 

We’re talking about any recent tattoos or piercings here, even if you didn’t experience any infections. These two additions to your body within the past year will keep you from being able to donate blood. 


There are some general health items that can keep you from being able to donate blood. 

People who are currently pregnant or recently gave birth are unable to donate. 

If you are anemic or have low iron levels in your body, then you won’t be able to donate blood. 

Being infected, whether with HIV, hepatitis, or a fever will prevent you from being able to donate. 

And if you weigh less than 110 pounds or you don’t pass the vital check at the beginning of your appointment, you won’t be able to move forward with a donation. 

Travel History

Your recent travel history can have an impact on whether or not you are able to donate. 

If you traveled to a malaria-risk country sometime in the last 3 years, then you won’t be able to donate your blood. 

And there you go! You are now fully equipped with all the things you need to know to answer that burning question of “Can I donate blood if I smoke weed???”

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