Can You Give Blood If You Smoke Weed?

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Are Cannabis Users Disqualified from Giving Blood?

There are many different ways to ingest cannabis. There is, of course, the good old-fashioned joint, followed by the equally good old-fashioned water pipe.

There’s also edibles, and tinctures, topical creams, and even THC bath soaks. The good news is, no matter how you enjoy your weed (with the possible exception of synthetic cannabinoids), you can give blood.

General Disqualifiers

When you go to your blood donation appointment, part of the process will include answering a bunch of questions about your general health, any medications you take, your sexual history, and your recent travel history. It is imperative that you answer these questions truthfully, as depending on the answers you provide, you may be disqualified from giving.

While this list is not complete, you will be disqualified if:

  • You have previously had the Ebola virus
  • You have some form of cancer of the blood, like leukemia or lymphoma
  • You have tested positive for HIV, or Hepatitis B or C
  • You have an inherited blood clotting disorder
  • You are feeling sick on the day of your donation
  • You are a user of illegal injection drugs or take them without a doctor’s prescription
  • You are a male who has had sexual contact with another male or males within the past 12 months
  • You have had a piercing or tattoo in the past 12 months.
  • You take blood thinners such as Warfarin or Heparin.
  • You take Teriflunomide, a drug that is used to treat multiple sclerosis
  • You take Dutasteride, a drug used in the treatment of an enlarged prostate
  • You take Isotretinoin, which is a drug used to treat acne

Additionally, you may be disqualified from giving blood for a period of time if you have recently traveled to a country or region where there is a high risk of malaria.

Do Blood Banks Test for THC?

Relax! You won’t be subjected to drug testing like you might for a legal proceeding or to start a new job. In fact, blood banks don’t test for THC – unless you consider their evaluating the condition of your eyes and the aroma that follows you in the door as a test.

The FDA, which regulates blood donation activities, does not require any form of testing. That being said, if a blood bank worker believes your appearance or behavior suggests you are experiencing the psychoactive effects of THC, she can disqualify you from making a donation at that time.

What Can Disqualify Someone from Donating Blood?

All of the general disqualifiers listed above can preclude you from donating blood at any given time. Additionally, you may be disqualified temporarily if you are pregnant or have recently given birth, or if your iron levels (and that’s one thing Red Cross workers DO test) are too low.

As for cannabis use, as noted earlier, you may be turned away if you are visibly showing signs of experiencing the psychoactive effects of THC.

This brings us to the subject of synthetic marijuana. There’s an argument to be made that synthetic marijuana, known in common terms as K2 or Spice, is not in actuality a real form of cannabis.

Close up of hemp buds

After all, it is a human-made substance similar in make-up to marijuana, but not a plant. Due to their mind-altering qualities, these synthetic forms are unregulated and placed in a group called new psychoactive substances (NPS).

If you have smoked or ingested any new psychoactive substance, the Red Cross will not allow you to make a blood donation.

There is one exception. Marinol, an FDA-approved medication that is used to treat certain side effects from chemotherapy or HIV infections, is made up partly of synthetic marijuana. I

f you are taking the drug because you have a medical condition, you cannot donate blood. However, because it is FDA-approved, if you are taking Marinol but don’t have a pre-existing condition, you would be not be deferred.

Other Requirements for Donating Blood

Every donor must meet certain eligibility requirements. In the United States, donors must be at least 16 or 17 years of age depending on the state and a minimum of 110 pounds. Donors must be in general good health and be feeling well on the day of their donation.

Additionally, at least 56 days must have transpired since their last donation.

How You Can Still Help If You’re Disqualified from Giving Blood

In some cases, a donor is disqualified temporarily from giving blood. Sometimes a donor’s iron level is too low on the day of the appointment.

Or, they may simply be feeling poorly that day. In other cases, people are permanently disqualified from giving blood, such as those who have an inherited blood clotting disorder or who have previously had the Ebola virus.

Whether your disqualification is short term or permanent, you can still do your part by making a monetary donation to the Red Cross or other blood collection agency.

Frequently Asked Questions

Q: Does the Red Cross discourage cannabis consumers from donating blood?

A: No! On the contrary, they welcome their donations as they do from all eligible donors. According to the Red Cross, about 36,000 units of red blood cells are needed every single day in the United States.

red cross

Red Cross workers know how badly blood is needed for accident victims, for those going through cancer treatments, and for a litany of other reasons. The Red Cross encourages all eligible donors who are healthy on the day of their appointment to give blood.

That includes cannabis users.

Q: Do I need to wait to donate after using cannabis, and if so why?

A: While there is no specific waiting period before a person who has recently smoked cannabis can give blood, a blood donor needs to be of sound mind when he presents himself for a donation. He needs to be able to answer questions and follow instructions.

If your use of cannabis is impairing your memory or your ability to comprehend what is happening around you, hold off donating until you are in a sober state.

Q: Doesn’t the Red Cross have to follow guidelines put out by the Drug Enforcement Administration—the same agency that classifies cannabis as a Schedule One drug?

A: Don’t confuse the U. S. Drug Enforcement Administration (DEA) with the U. S. Food and Drug Administration (FDA). It is the FDA that regulates whether or not people are eligible to donate blood.

The FDA does not require blood collection agencies to test donors for THC in their systems.

Bottom Line

Giving blood is a good thing to do, so if you’re healthy and meet the eligibility requirements to give blood, by all means, roll up a sleeve and participate! You’ll not only help to save lives but you’ll also get fed some extra goodies when you’re done.

Just make sure you hold off on your cannabis use for a period of time before your appointment. How long will THC stay in your system?

If you’re an infrequent user, 12 to 24 hours should be sufficient for it to work its way out of your body. If you use it more regularly, give it three days.

And if you’re a bonafide stoner, waiting a few weeks is best. The important thing is to go to your appointment as “clean” as you can possibly be and with a clear and conscious mind.