Are you wondering if it’s possible to test for marijuana with a mouth swab drug test? We’re here to break down how to test for marijuana compounds, specifically THC or Tetrahydro-cannabidiol.

Imagine landing your dream job, agreeing to everything, but then being asked to take a drug test. If you are a marijuana user, or have tried any products containing THC, you may worry if a mouth swab drug test will detect it and cost you the position. Luckily, if your concerns are centered solely around THC and you’re willing to take a break, you can still take the drug test with confidence and start your new position. But you should consider when the drug test can detect THC and for how long, so that you can maximize your chances of passing the test or any you are subject to in the future. Read on to learn more.

How Do Mouth Swabs Work?

A mouth swab drug test uses a stick that has an absorbent pad or sponge on one end. Someone else, besides yourself, should administer the test to make sure the results are accurate.

The individual collecting your saliva should know how to do the test properly, making sure cheating is not a possibility. They’ll insert the end of the stick with the absorbent material to collect enough of a saliva sample for the test.

Depending on where you go, the testing center may analyze the results there, or they may send the results to a lab. Once the results come back, you and whoever ordered the test can use your results to move forward.

Are Mouth Swabs Accurate?

For the most part, mouth swab tests are between 97 and 98% accurate. The accuracy rate can depend on a few factors, such as the type of drug test they used and the materials of the swab. Other factors include:

  • Drugs they want to test for
  • Collector’s experience and skills getting saliva
  • Skills and quality of the analysis

Whether you’ve consumed marijuana compounds or not, the test should be able to determine if you have consumed drugs recently. Now, if the test doesn’t test for THC, it may not detect anything, even if you just used it. Before you have a drug test, you can ask what substances they will look for during the analysis. Then, you can prepare for the test so that you have the best chance of passing it.

Can the Test Detect THC?

Some mouth swab tests can detect THC, but some can’t; it all depends on the type of test. One mouth swab test may focus on THC, while another looks for cocaine or opioids. A multi-panel drug test can detect multiple drugs in your saliva. If the test can detect THC or other marijuana compounds, you will need to avoid those for a while before the test.

It doesn’t matter if you normally consume Delta 8, use a THC vape pen or add marijuana to brownies. You can learn more about certain cannabinoid compounds here, so that you can adjust when you consume marijuana before a mouth swab drug test.

Detection Timeline for THC

The drug detection timeline for THC in a mouth swab drug test is relatively short. You can detect THC

in your saliva shortly after you consume it, however, THC can leave your saliva within 24 hours.

That being said, you can’t necessarily use the same timeline with other drug tests (or substances). If you ever need to do a breath test, that will have a shorter timeline of only a few hours of detectable THC. On the other hand, a blood test can detect THC for up to three weeks after you consume it. Similarly, you may be able to detect THC in a urine sample test for up to a month, and a hair sample can hold THC for even longer.

If you can choose which type of drug test, a mouth swab can be a good option. Then, you won’t have to go as long without consuming marijuana. In other words, avoid the hair test if possible.

Can You Beat a Mouth Swab Drug Test?

Some people may try to beat the mouth swab drug test so that they can still pass without giving up marijuana beforehand. While it may be possible to pass the test this way, it’s not very likely and is not recommended. You can try using a ton of mouthwash to get the THC out of your saliva. Brushing your teeth a lot between taking THC and your drug test may also help. Another option is to drink a lot of water to flush the THC out of your mouth.

However, these methods aren’t always going to work. They may be effective if the person administering the test doesn’t take a ton of saliva or if the analysis isn’t overtly accurate. It may also miss the THC because of the slight failure rate of mouth swab drug tests. Either way, the best way to beat the test is to avoid THC for at least 24 hours before the drug test. That way, you can make sure it’s out of your saliva and your job is guaranteed.

Related: Are you curious about the history of cannabis in America and how we got to where we are today? Click here to learn more about THC and CBD, and how their uses have developed through the ages in the United States.

What to Expect When You Have to Take a Drug Test

If you’ve never had to take a mouth swab drug test, it can be a bit stressful. While recreational marijuana is legal in some states, it can still be controversial to have positive results for marijuana compounds.

The exact process will depend on where you go for drug testing and who gives the test. Even within one testing center, the process may vary based on who is working that shift. Here are a few things to know when you have to go in for a mouth swab drug test:

Before the Test

You may need to arrive early for your testing appointment. You can then sign in and fill out any necessary paperwork. You may also have to sit for 10 minutes, and the testing center may watch you to make sure you don’t eat or drink anything. The waiting period gives your saliva a chance to get rid of any food or dilution from water. That way, you can get the most accurate results possible. Even if you don’t have to wait 10 minutes without food or water, it’s not a bad idea. If the analysis has issues, you may need to get another test.

During the Test

In most cases, someone else will help to swab your mouth for the test. For one, this allows the collector to control each step and avoid contamination. Even if you’re honest, some people may try to switch out the swab or do something to lie on the test and get favorable results. The person collecting your sample will swab your cheek to get as much saliva as they need. You will have to sit there with your mouth open as they collect your sample. Then, the collector will safely store the sample to be sent off to a lab for analysis.

After the Test

After you take a mouth swab drug test, a technician will analyze it. They may find THC or other drugs, depending on what the test looks for and what you’ve recently consumed. You should then get a call or message with your results; you may get the call within a day or two. The timeline can depend on the testing center and the lab and how many tests they have to run. Once you get your results, if they are not automatically shared with your employer you can send them in and begin your new position, given the test results were as desired. If you are taking the precautions mentioned above, you should be able to pass the mouth swab test looking for THC, no problem.

Why Would You Need a Mouth Swab Test?

If you’ve never had to get a drug test, you may not realize the reasoning for it. In some cases, the reason is clear, such as after a bad car accident or if a cop stops someone for reckless driving.

However, it can still help to look at some common reasons for needing to test for cannabis components or other drugs. Here are just a few of the most widely seen reasons for drug tests:

Starting a New Job

Starting a job can be an exciting time, especially if it’s a job you really want. Some employers may require a background check, and you may need to take a drug test. Your new employer may give you directions on where to go for your drug test, or you may have some choice. Either way, make sure you get the drug test so that you don’t have to put off starting work. Depending on your job, you may also need to take a drug test after an extended period away from work. This could happen if you go on parental leave or are on furlough for a while.

Give yourself enough time to do the drug test before you plan to start work. That way, the lab can analyze the results and confirm you’re ready to go.


Once you start a job, you aren’t out of the woods regarding drug tests. Some employers may want to test for drugs if they suspect you or any employee in general, has been doing drugs. Perhaps your employer finds marijuana in the break room. If they can’t narrow down whose it is, they may test the entire team. Or if they see you acting “high” while at work, they may ask you specifically to get a drug test. While this type of test can be scary, especially if you just consumed cannabis components, you may be fine with a mouth swab drug test. Make sure you follow your work’s drug policy so that you can pass any tests after you start working.

Random Employment Testing

Your employer may also implement random drug testing. Keeping the tests random means employees can’t prepare for it aside from abstaining from drugs entirely. However, it can be hard if you need to use marijuana for medical reasons. If you do need to use it for medical purposes, you may be able to get an exemption from random testing, but it’s still something to consider in the workplace.

Participating in a Sport

If you’re part of a professional or collegiate sport, you may need to get a drug test. Sporting teams and associations may require drug tests to make sure players aren’t taking drugs that give them an unfair advantage. Some coaches may also want to make sure players aren’t taking any drugs aside from prescriptions. You should ask your coach or organization about drug testing requirements. Then, you can make sure you pass the drug test so that you can play or participate in the sport during your next game or match.

Forensic Investigation

After a car accident or another crime, a police officer may ask you to take a drug test. Because some drugs can impair your ability to drive, testing for drugs can rule out those causes when determining the accident’s cause. Sometimes, these tests will use your breath rather than your saliva. However, you may need to do a mouth swab drug test after another crime or for police to use as evidence.

While you can refuse the test under some circumstances, taking it can be a smart decision. Then, you won’t have to deal with answering why you didn’t want to take the test in the first place.

Medical Use

If you use or take medical marijuana, your doctor may want to monitor your levels to make sure the drug is working. Your doctor may want to run a swab test at your appointment, and then they can compare the drug concentration with your symptoms. Depending on the results, your doctor may give you a new recommendation for consuming marijuana, or they may adjust other treatment recommendations to use with cannabis. One of those options could include replacing THC with CBD, which depending on the product, could have zero THC but still deliver therapeutic benefits.

Can You Refuse to Take a Drug Test?

No one can force you to take a mouth swab drug test or any other drug test. However, taking a drug test can be a condition of things such as employment or the ability to retain your driver’s license.

If you refuse to take a drug test, a company can refuse to hire you. Law enforcement can also suspend your license. Depending on organization rules, you may not be able to play in an upcoming game or match for your favorite sport.

Before you refuse a drug test, you should consider how it may affect you in the long-term and if those effects are worth it. You may decide it’s better to take the test so that you can start your dream job or play in your next game without delay.

Using a Mouth Swab Drug Test for THC

A mouth swab drug test can be a great way to test for THC. However, it does have a small detection window, which could play in the testees’ favor. After about a day, you may not be able to find THC in saliva, but it can still show up in blood or urine samples. Fortunately, the short testing window can make it easier to pass a mouth swab drug test. Of course, passing a drug test for any reason is always important, but make sure you are being safe in your marijuana use and complying with your employer, team or local governments regulations at all times, not just before a drug test.

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