Donating plasma is a lifesaving and admirable act; plasma is a crucial blood component, and donated units of plasma can be used to treat numerous health conditions.
But as marijuana legalization becomes more widespread and more people use cannabis to discover relief from their own health conditions, the question arises: Can you donate plasma from smoked weed?
In this guide, we’re breaking down everything you need to know about donating plasma and smoking weed. But the short answer is yes—you can donate blood (and blood components like plasma and platelets) if you smoke weed.
While you can’t donate while you’re intoxicated, donating if you’ve recently smoked is safe.
Understanding Plasma Donation
Plasma is one of four major whole blood components—the others being red blood cells, white blood cells, and platelets.
Plasma is a liquid that carries compounds that are key to:
- Blood clotting after an injury
- Immune system function
- Electrolyte transport around the body
When donating whole blood, a donor’s blood moves through a tube and into a sterile collection bag. But when donating plasma, the donor’s blood moves through a tube into an apheresis machine.
This machine separates the plasma from the rest of the blood, moves the plasma to a collection bag and returns the other components back to the donor (along with some sterile saline).
Donated plasma is then administered to a patient in need via a blood transfusion. Plasma units are often given to patients suffering from:
- Severe burns
- Clotting disorders
- Severe liver disease
Donors only provide about 32 ounces of plasma per donation—for the average person, that’s less than 20% of your total blood volume and only about 30% of your total plasma volume. Your plasma levels return to normal within 48 hours of donating.
The Influence of Marijuana on the Body
Marijuana, also known as cannabis, impacts various bodily systems. Cannabis can contain one or more active compounds called cannabinoids: THC and CBD are the major cannabinoids, and these are most commonly found in marijuana products.
People who smoke weed, eat edibles or use vaporized products (like oils or wax) report effects such as relaxation, pain relief, and altered perception while using marijuana.
Since it’s the only compound in cannabis that’s psychoactive, let’s focus on THC:
- THC concentrates in the blood soon after smoking or ingestion, but 85% of the THC introduced to your body is eliminated via waste within 24 hours.
- The other 15%, however, is stored in your body’s fats. Stored THC returns to the bloodstream (and is then eliminated) relatively slowly and in low concentrations.
- While it can take time to be completely eliminated from your system, THC won’t continue to produce intoxicating effects after a large dose wears off. So, after smoking weed, you can expect some concentration of THC to remain in your bloodstream for multiple days. The duration depends mostly on how frequently you smoke.
Who Can Donate Plasma?
Blood donation eligibility can be complex, and misinformation is rampant. But there are a few important things to note about blood donor eligibility:
- Donation criteria are the same for all types of blood donations: whole blood, platelets, plasma, and double red cell donations.
- Donation criteria are overseen directly by the US Food and Drug Administration (FDA). Blood is a highly regulated product in the US—and for good reason.
- Local blood centers (facilities that collect blood donations, test donated blood, store units, and transport them to local hospitals) must abide by the FDA’s guidelines for donor eligibility. But blood centers can also create their own eligibility criteria in addition to the FDA’s guidance.
To find out if you’re eligible to donate plasma, explore your local blood center’s eligibility criteria online or talk to a blood center staff member in person.
Marijuana Use and Plasma Donation
The FDA currently does not have any published guidelines related to marijuana use and blood donation eligibility. So, technically speaking, you can donate plasma if you smoke weed.
However, there are a few important things to remember if you’re a regular cannabis user looking to donate blood:
- You can’t donate blood if you’re intoxicated – Technically speaking, donating blood is a voluntary medical procedure—voluntary is the operative word. To ensure 100% donor consent, blood centers do not let people who are visibly intoxicated donate blood. So, if you’ve used a cannabis product containing THC within the last few hours and you appear to be under the influence, staff will likely ask you to come back another time.
- Some individual blood centers have specific eligibility criteria – Some blood centers enforce additional eligibility criteria on top of the FDA guidelines. The FDA does not have any cannabis-related regulations in place, but your local blood center might. It’s very important to check the eligibility criteria before you try to donate.
- Blood centers are highly unlikely to test units for cannabis – Blood center laboratories must perform numerous mandatory tests on all units of donated blood. They test units for bloodborne illnesses like HIV, create in-depth antigen profiles for patient compatibility matching, and more. These tests aren’t free, and they require time and (inmost states) licensed staff. It’s very unlikely that your local blood center is testing units for THC—but it’s not impossible.
If you’re a cannabis user looking to donate plasma, all you need to do to ease your worries is check your local blood center’s eligibility requirements (and wait until you aren’t under the influence to donate).
Legal and Ethical Aspects to Consider
Marijuana is still illegal at the federal level. So, blood centers that choose to bar marijuana users from donating might have legal grounds to do so. But marijuana-related policies aren’t just uncommon in blood centers because of the testing implications.
They’re also unlikely because:
- Blood is in short supply – Someone in the US needs a blood transfusion every two seconds. Blood is in high demand—and often in short supply. Blood centers are motivated to recruit as many eligible donors as possible to meet the needs of patients in their local hospitals. Barring cannabis users from donating for that reason alone wouldn’t help them accomplish this goal.
- Cannabinoid concentrations in the blood are low within hours of smoking – Within 24 hours of smoking, only 15% of the THC you ingest remains in your system—and that 15% returns to your bloodstream very slowly. When you donate blood, you’re not giving anywhere close to the majority of your blood volume. While there aren’t currently any studies to support this, any concentration of THC in a donated unit of blood is likely to be negligibly low.
If you have ethical concerns about donating blood after smoking weed, consider the second point above. Current evidence suggests that there is no harm in donating blood as a marijuana user as long as you aren’t intoxicated while donating and you meet your blood center’s eligibility criteria.
Wrapping Up: Plasma Donation and Weed Use
Ultimately, the answer to whether you can donate plasma if you smoke weed is not definitive—it largely depends on the specific policies of your local blood center.
If you’re a marijuana user considering donating plasma, it’s best to ask the center directly about their policies.
The most important criteria for blood donation eligibility is feeling healthy and well—and feeling healthy and well should be a top priority, whether or not you’re planning to donate blood soon.
If you’re looking to improve your quality of life with medical marijuana, TeleLeaf can help. We understand your journey because we’re patients ourselves, and we’re passionate about empowering people with the life-changing, therapeutic potential of medical cannabis.
Learn more about TeleLeaf’s mission and discover how medical marijuana could unlock a better quality of life for you.
Can Marijuana Users Donate Plasma?
The ability to donate plasma if you smoke weed largely depends on the specific policies of your local blood center. While very few centers might defer marijuana users, the vast majority do not test for marijuana or defer cannabis users. To determine eligibility, it’s recommended to inquire directly with your chosen donation center about their stance on marijuana use.
American Red Cross. Can You Donate Blood if You Use Cannabis?
National Library of Medicine. Physiology, Blood Plasma.
American Red Cross. Types of Blood Donations.
American Red Cross. Blood Components.
US Department of Health and Human Services. The Process for Giving Plasma, Step-By-Step.
Iranian Journal of Psychiatry. Chemistry, Metabolism, and Toxicology of Cannabis: Clinical Implications. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3570572/
American Red Cross. The Importance of the Blood Supply.