A burning question on many prospective CBD users' lips is…

"Just how long does CBD stay in your system?"

This is a fair question, to be sure, as people are curious about the effects of CBD and how long they last. You might also be looking for the answer because you are worried about being drug tested at work or school, and as CBD is a cannabis derivative, it's understandable to be concerned about it showing up.

Unlike THC (the 'high' inducing cannabinoid), which has been extensively studied in terms of how long it stays in your system, CBD has not been as closely researched. This is due in part to the fact that CBD does not have psychoactive properties like THC, and also because CBD is not regulated in the same way as THC. More on this later.

In today's write-up, we will dive deep into the world of CBD and look at what the currently available science has to say in terms of how long it stays in your system. We will also look at factors that can affect the duration of CBD's effects and how (and even if) you can estimate when it may leave your body completely.

How long does CBD stay in your urine?

The most common form of drug testing is urine testing. Urine testing usually looks for metabolites, which are the by-products that result from your body breaking down and processing substances. These by-products can stay in your urine for some time after you have ingested CBD.

The length of time CBD stays in your urine varies depending on a few key factors that we will discuss a little further down (such as frequency of use, dosage, and body weight). However, as a general rule of thumb, a single dose of CBD can stay in your urine for up to 5 days at least.

urine in a medical cbd test tub

How long does CBD stay in your blood?

Blood testing is the gold standard of drug testing, and while they are rarely used in routine screenings, they are more accurate than urine tests and can detect smaller amounts of substances.

The duration of CBD in your blood is influenced by the same factors mentioned above, and while the scientific community are still unsure about exactly how long CBD stays in the blood, we can look at this study from December 2022.

Modelling in this research review, which looked at three major CBD studies, found that "every 100 mg increase in the dose of CBD provided extends the window of detection by ~4 days."

The authors also conclude that "Doses of 100, 300 and 600 mg are, therefore, predicted to persist in plasma for an average of ~5, 13 and 25 days, respectively." and that "one-off doses in the ‘nutraceutical’ range (e.g., ~15 mg) appear to have limited persistence."

This alludes to the fact that a small or infrequent dose of CBD is likely to be out of your blood in a matter of days, but the higher the dose and more frequently you take it, the longer it may last.

How long does CBD stay in your saliva?

Not very long at all. Depending on how often CBD has been taken in the previous few days, and the dosage size, a saliva test (that is actually looking for CBD) may be able to detect CBD for up to 36 hours after the last use.

Will CBD show up on a drug test?

Now, this is where all of the info above really comes into play. The short answer is…

No, CBD will not show up on conventional drug tests, but this comes with a huge caveat.

CBD products come in three main subtypes: Full-spectrum CBD, broad-spectrum CBD, and isolate CBD. As you might suspect from the names, the products containing the last of the three will never show up on a drug test that is looking for THC, but the first two could.

Full-spectrum and broad-spectrum

These are made using either the whole hemp plant or just the flowers minus the THC. While the majority of compounds here will be other cannabinoids and terpenes, there is still a chance that trace amounts of THC may make their way into the mix.

Broad-spectrum CBD products should have all of the THC eliminated, whereas full-spectrum products are legally allowed to contain a minimal percentage of THC. In the US, both full and broad-spectrum CBD products sold over the counter must contain less than 0.3% THC, and it is extremely unlikely (but not unheard of) that this will show up on a drug test. In other countries, including most of Europe and the UK, that level is 0.2% THC.

However, if you are a heavy user of full-spectrum or broad-spectrum CBD and are tested within a few days of your last dose, you might risk being detected. The chances are pretty low, but they are still there.

If you are growing your own CBD cannabis strains the safest way to avoid THC is to grow varieties that have a low THC percentage. Strains such as Ringo's Gift and ACDC have THC levels as low as 1% and CBD levels around the 20% mark. As far as effects go, you will not feel the effects of THC when smoking these strains.

Isolate CBD

Isolate, as the name suggests, is pure CBD, and because it doesn't contain any THC, you have no risk of it showing up on a drug test.

What affects how long CBD stays in your system?

There are a couple of factors that can have a surprisingly significant effect on how long CBD stays in your body. When talking about the time it will take for a drug to leave the human body, the term 'half-life' is often used.

This refers to the amount of time it takes for half of a dose to be metabolized (broken down and processed by the body). For the drug to clear the human system entirely, it takes roughly four to five half-lives.

So, what is the half-life of CBD?

Well, that is again dependent on the factors we are about to discuss, but in general, the half-life of CBD is anywhere between 2 and 10 hours if taken in oral spray form, 2 to 5 days if taken orally for an extended period, or around 30 hours when smoked.

Usage frequency

The total amount of times you take a CBD product each day, week, or even month can have a real effect on how long it lasts in your body. This principle is known as 'accumulation' and is mostly due to the fact that cannabinoids (including both CBD and THC) are fat-soluble. This means that if you are regularly taking CBD, it can slowly build up in the body to a point where it can take much longer to be cleared.

How much you consume with each dose

The amount of CBD you are taking at one time will also contribute to the length of time it takes for your body to process it and get rid of it fully. The higher the dose, the longer it may take to leave your system. This is especially true if you are taking high doses regularly.

How you consumed it

The method by which you take or consume the CBD can have a big impact on the time it will take to clear. For example, if you take it orally as an oil or capsule, it will be processed by the liver and digestive system before entering your bloodstream. This can take a little longer than other methods like vaping, or smoking CBD weed where it is inhaled into the lungs and absorbed directly into the bloodstream. Sublingual application (where CBD oil drops are placed under the tongue) is another fast-acting method.

Your diet

While not a specific factor related directly to CBD, it's important to note that diet and exercise can also have an effect on how long CBD stays in the body. A healthy, well-balanced diet with plenty of water can help to speed up your metabolism and clear substances from your body more efficiently.

However, there is research to show that people who take CBD on an empty stomach, especially if it is taken in edible form, may have an increased half-life. This means that the less you eat alongside CBD, the faster it will leave your system, except when it comes to high-fat foods.

This 2019 paper showed that people who took oral CBD alongside high-fat foods, such as fried foods or those with high oil content, had higher CBD exposure and absorption in their blood than those who took it on an empty stomach. So, while a healthy diet can help, you should avoid taking CBD with fatty meals if you want it to leave your system quickly.

How long does it take for the effects of CBD to take hold?

CB1 and CB" receptor locations on the human body that up the endocannabinoid system

Again, there's not a 'one size fits all' answer to this question. This is very much dependent on firstly the way you decide to take your CBD, but also the rest of the factors discussed above.

When CBD oil is vaped or taken sublingually (under the tongue), it will typically take between 15-30 minutes for the effects of CBD to be felt. If you are smoking high percentage CBD flower, the effects will kick in a little quicker.

It will take a fair bit longer if you are eating your CBD. When taken orally, your body will need to break down the edible or capsule and process it in the liver before it enters your bloodstream. This can take between 30 minutes to an hour for you to start feeling anything.

The effects of CBD also depend on your unique body chemistry, so there is no one-size-fits-all answer. Some people may take longer to feel any effects, while others may experience them almost instantly.

How long will the effects last?

Just like pretty much every other aspect we've discussed, how long the effects of CBD will last is hard to nail down and is dependent on the above factors. Generally speaking, though, the effects of a single dose of CBD should last between 2 and 7 hours.

How can I flush CBD out of my system?

There are a few tricks that you can use to potentially help speed up the process of getting CBD out of your body. A mostly healthy diet is important, and drinking plenty of water (more than half a gallon a day) will help get rid of any substances in your system quickly.

Diuretics are a popular way to flush CBD out of your system quickly. These are chemicals that promote the production of urine, which can help clear CBD and other substances from your body faster. Some natural diuretics include caffeine, cranberry juice, and dandelion tea.

Heavy, vigorous exercise can also help to increase your metabolism and can lead to CBD being cleared from the body a little faster. Some people suggest taking vitamin C supplements, as this has been shown in a small body of research to help speed up the elimination of cannabinoids from the body, but the jury is still out on this one.

There are a few different products available online that claim to help cleanse your body and flush out cannabinoids (usually targeting THC), but these are not scientifically proven and may not work for everyone. These include drinks, pills, and teas marketed as 'detox' products. Do your research before purchasing any of these products, and keep in mind that they may not be effective.

At the end of the day, there's no surefire way to flush CBD from your system completely, but a combination of healthy habits and some of the tips discussed may help speed up the process. Just remember, everyone's body is different, so what works for one person may not work for you, and if passing a drug test is a concern, it's best to avoid any full or broad-spectrum CBD products to be safe, and just stick to isolate.

How long does 500 mg of CBD stay in your system?

As discussed earlier, there's no definitive answer for how long CBD stays in your system, as it depends on various factors. However, let's take 500 mg of CBD as an example and make some assumptions to give you a general idea.

Let's assume that you take 500 mg of CBD orally in capsule form. As we mentioned before, this method takes the longest for CBD to be absorbed and processed by the body. It can take anywhere from 30 minutes to an hour for the effects to kick in.

Let's also assume that you have an average body weight of 150 to 200 pounds and a healthy liver function. Going off the average half-life of CBD, which is around 2-5 days, it would take approximately 10-25 days for the CBD to leave your system completely. This is also assuming that you have been taking 500 mg of CBD regularly and not just a one-time dose.

Again, this is just a rough estimate and can vary based on individual factors.

How long does 10 mg of CBD stay in your system?

10 mg of CBD is a relatively small amount, and the effects will likely not be as long-lasting as a higher dosage. The CBD should also clear your system in a much shorter period of time, but if you have been taking a small dose for an extended period of time, it may take longer for the CBD to leave your system completely.

If you are a first-time or infrequent user taking 10 mg of CBD orally, it may take around 2-3 days for the CBD to clear your system. However, if you have been taking 10 mg of CBD regularly for a few weeks or more, it may take up to a week for it to completely leave your system.

How long does edible CBD stay in your system?

CBD edibles in a glass jar

CBD products that are eaten, such as gummies, chocolates, or capsules, will take longer to be absorbed and processed by the body, but they will also last longer. The effects of edible CBD can be felt for 4-8 hours, but it may take anywhere from 30 minutes to an hour for the effects to kick in.

In terms of how long the CBD stays in your system, it will likely follow a similar timeline. If you are a first-time or infrequent user, it may take 2-3 days for the CBD to clear your system, while regular use may result in the CBD staying in your system for up to a week.


So, there we have it, a pretty extensive overview of how long CBD may stay in your system. While there's no definitive answer and a bunch of factors at play, understanding elements such as dosage, method of consumption, and personal body chemistry can give you a general idea of how long the effects may last and how long it takes for CBD to leave your system.

It's important to remember that everyone is different, so these timelines are not set in stone and can vary from person to person. If you are concerned about CBD showing up on a drug test, it's best to consult with your healthcare provider and consider avoiding full or broad-spectrum products. And as always, be sure to do your research and purchase high-quality products that have real user reviews and some kind of certificate of analysis available so you know exactly what you're putting into your body.