Will CBD Oil Show In Blood Tests?

It's pretty evident that if you have cannabis that contains THC, you will test positive for marijuana. But what about CBD?

Maybe you're interested in trying a CBD product like CBD oil, and you're wondering, will CBD oil show in blood tests. A blood test isn't that common for marijuana testing, but this is a common question people have regarding drug testing and CBD oil.

Today you'll find out everything you need to know about CBD oil and four reasons why you may fail a blood test.

CBD oil in a nutshell

CBD oil is a supplement that people use to aid with physical and mental symptoms of different conditions. When you take it, it interacts with your Endocannabinoid System (ECS) and gives you therapeutic effects.

The main effects of CBD are:

  • Anti-anxiety and reduces depression
  • Reduces chronic pain
  • Aids sleep problems and insomnia
  • Treats neurological disorders

How CBD oil is made

The product itself has extracted cannabinoids from the cannabis plant, and it's placed into a carrier oil to help with the absorption of those cannabinoids.

Hundreds of compounds exist within the cannabis plant, but the main two are THC and CBD. During extraction, it can be further distilled by removing THC entirely or isolating CBD itself. This creates different types of CBD oil, which can affect drug testing. More on that later.

Hemp Vs. Marijuana

Hemp and marijuana are both strain types of cannabis. They are mostly the same thing, except they have different levels of THC.

Marijuana has higher levels of THC with lower levels of CBD. However, hemp has higher concentrations of CBD and little to no THC.

When you purchase a CBD oil product, it will usually derive from hemp instead of marijuana because of the high levels of CBD. There are very few strains of marijuana that have high levels of CBD.

CBD oil vs. cannabis oil

CBD oil and cannabis oil may sound similar, but they are sold differently.

Cannabis oil is usually sold only in dispensaries where you need a medical card to buy it. However, CBD oil is sold as a dietary supplement that you can buy almost anywhere, without the need for a medical card.


THC is the primary compound in marijuana strains that give you that 'high.' When you smoke marijuana, the THC stimulates the CB1 receptors in the ECS, which makes you feel this way.

CBD itself does not produce this psychoactive effect at all. No matter how much CBD you take, you will not experience a psychoactive effect.

CBD doesn't affect the ECS the same way as THC. All it does is increase the activity in the ECS, but it doesn't directly stimulate it. Its main function is to bring the body back into homeostasis so that everything is balanced.

Some products might contain THC

The CBD market

The main reason why people are failing is, the products they're buying may contain more THC than the standard limit.

But I thought CBD oil had little to no THC? Well, since the 2018 Farm Bill, hemp has been allowed to be produced and sold as long as it contains less than 0.3% THC.

So why do some CBD oil products have more THC? Well, unlike the cannabis market as a whole, CBD is rarely regulated by the FDA. This makes it difficult for consumers to know what's in it. The only way for you to find out is to make sure that the product is third-party lab tested.

Types of CBD oil

Three types of CBD oil play a role in failing a drug test. Make sure you read carefully, so you understand what the differences are.


When hemp goes through the extraction process, all the cannabinoids, terpenes, and flavonoids are separated from the plant material. This is also known as a full-spectrum extract because it contains everything.

It's then placed into a carrier oil such as hemp seed oil or MCT oil. This is the type of CBD oil that you need to double-check. If it's not lab-tested, then you have no idea how much THC is in product regardless of the label.


After a full-spectrum extract, companies may use a method called distillation to remove THC altogether. With no THC present, it makes it nearly impossible to fail a drug test.

You must still make sure it's third-party lab tested just to be safe.

CBD isolate

CBD can be isolated by removing all the cannabinoids, terpenes, and flavinoids after a full-spectrum extract. This usually appears as a white powder which is added to carrier oil.

Again, it's nearly impossible to fail a drug test because it has no THC present.

Will CBD oil show in blood tests?

CBD itself will not show up in any drug test because it's not seen as a drug. CBD has no psychoactive effects like THC, which causes impairment.

The police wouldn't stop you because you have CBD in your system. CBD would show up in a blood test if someone were to see if there is any CBD in your system. But this information isn't relevant to anything.

No authority or workplace will take any action because you have CBD in your system. What you should be worried about is THC because that's what makes you test positive for marijuana.

Will 0.3% THC show up in blood tests?

There are some types of CBD oil products that contain little amounts of THC, such as full-spectrum. However, this isn't enough THC to cause impairment or make you fail a drug test.

How much THC makes you fail?

different drug testing for thc


Urine testing is the most common, especially in the workplace.

To test positive for THC, 50 nanograms per milliliter must be present. The results would be displayed as 50 ng/ml. A nanogram is around on-billionth of a gram.


Blood testing is the least common, which is unlikely to happen at your workplace. The main reason is that there a shorter window for testing positive compared to urine. You would probably be tested for this if you were stopped for driving under the influence.

It's only detectable in your blood for up to five hours. However, THC metabolites can be found for up to seven days.

Testing positive has different rules in different states. Some have zero-tolerance policies, whereas some others allow some THC.


Again this is another type of testing that isn't too common.

The Journal of Medical Toxicology suggested that 4 ng/ml would make you fail for THC. THC is found in the saliva for about 72 hours, but maybe longer, depending on how much you use it.


There isn't an established limit when testing THC metabolites in the hair. Again this isn't a standard testing method, but it can show THC metabolites for up to 90 days.

Ways that CBD oil can show up on blood test

ways that thc shows in blood test

Here are four ways that THC can show up on a blood test from taking CBD oil.

1. Secondhand exposure

It's unlikely that you'll test positive for marijuana from simply being exposed to it. However, if you're in a household or environment where people are smoking a lot, you could be passively inhaling it.

2. Cross-contamination

Cross-contamination can occur during the CBD manufacturing process. CBD oil may be around other products that contain THC, which could cause this to happen.

3. Untrustworthy brand

As CBD is an unregulated market, some companies don't even lab-test their products. So whatever their label says can be false because you have no idea what the cannabinoid profile of the product is.

4. Dosage

Taking extremely high doses of a full-spectrum type of CBD oil can make you fail a drug test. This isn't common, and you would have to take an extremely high dose for this to happen.

How to make sure your CBD oil doesn't make you fail


If you're worried about failing, make sure your product is third-party lab tested. This will tell you the exact cannabinoid profile of the product. It checks for not only THC but also contaminants and other impurities that may be present.

Avoid full-spectrum

Even though some full-spectrum products are third-party lab tested, you may want to avoid it altogether. For peace of mind, it's better to opt for a broad-spectrum CBD oil product.

Frequently Asked Questions

Can CBD oil be detected in blood tests?

Can CBD turn into THC in the body?

How long is CBD detectable in urine?

Can CBD lotion make you fail a drug test?

Nabrissa Simpson

I'm the co-owner of CBDTornado. I live in Star, Idaho and CBD oil has got rid of my anxiety and muscle pains. I take 50mg a daily and haven't looked back since.

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