Proven Ways to Pass a Mouth Swab (Saliva) Drug Test

Daniel Miller, Ph.D Pharmacology, Drug Testing Specialist

Last updated on May 11, 2024

A mouth swab drug test can only detect the use of marijuana in the last 3 days. So if you last smoked a week ago, you are safe.

After smoking marijuana, some of the Delta-9 THC or Delta-8 THC sticks all over the surface of your mouth. All you need to wash out that THC to pass the mouth swab drug test.

The best thing about this method is that you can use just water, and that’s backed by science. I will dive into this topic in this article.

I will explain the methods proven to work and that have helped over 50,000 people pass the mouth swab drug test.

How to pass a mouth swab drug test: step by step instructions

You’ll need one of the following:

• 3% hydrogen peroxide mixed with water (70% peroxide, 30% water)
• Listerine (alcohol-free)
• Plain water

If you are using hydrogen peroxide:

1. Rinse your mouth with the hydrogen peroxide mixture for one minute right before the test.
2. Repeat this step 3-4 times.
3. Rinse your mouth with water afterwards.

Listerine:

1. Pour 4 ounces (about 4 teaspoons) of Listerine into a cup.
2. Swish and gargle thoroughly for at least 30 seconds.
3. Spit it out. Repeat 3-4 times before the drug test.

Remember, don’t use Listerine with alcohol as it will make you fail the test for EtG.

Water:

1. Rinse your mouth with water for one minute before the drug test.
2. Repeat this 5-10 times.

Important tips for success

If you have a few days before your drug test, follow these tips to boost your chances of passing:

• Drink plenty of water: Keep swishing water around your mouth, rinse, and repeat. This also keeps your saliva flowing and helps wash out THC.
• Practice good oral hygiene: Brush your teeth twice daily, use mouth rinses, and chew anti-cavity gum after using weed.
• Eat fatty, fried foods: Since active THC binds to fats, eating these foods can help draw THC out of your mouth.
• Abstain from using weed: Avoid using weed for at least 48 hours before your test.

Since your employer might spring a mouth swab drug test on you randomly, it’s a good idea to keep a small bottle of detox mouthwash handy.

These are easy to carry, simple to use, and no one will think it’s odd if you’re swishing some mouthwash during a break.

How does this method work

I’ll discuss marijuana here, but the explanation also applies to other drugs and alcohol.

When you consume weed, THC gets into the blood through the lungs or the stomach walls(if you use edibles).

After that, it is metabolized and excreted. But it never gets into the saliva.

The only THC in your mouth is THC that sticks to your mouth during smoking.

Traces of weed are detectable in saliva for up to 3 days after the last toke. Other drugs are detectable for up to 10 days.

A 2014 study published in the Journal of National Institutes of Health focused on the effects of various mouthwashes on the THC levels in saliva.

I’ll explain how this study assessed the effectiveness of different substances like water, whole milk, and a hygiene product called Kleaner in reducing THC in saliva. This information is especially important for drivers, as many places test a driver’s saliva for drugs.

The study lasted four days and included 11 regular cannabis users. These participants smoked their usual amount each day. Researchers collected saliva samples multiple times each day, both before and after smoking, to measure THC levels.

On the first day, participants rinsed their mouths with water before each test. The next day, they used either Kleaner or whole milk. By the third day, they returned to using water.

The results showed that rinsing with water significantly reduced THC levels immediately after rinsing.

As the study suggests, rinsing your mouth with any liquid, like hydrogen peroxide, Listerine, or water, can effectively lower the amount of drug metabolites in your saliva.

Why should you use detox mouthwash, and how does it work?

Detox mouthwash combines with oral fluids and uses fast-acting ingredients to clean your mouth of unwanted toxins.

The great part is that adulteration tests can’t detect these ingredients, so you won’t get caught cheating.

However, there are a few things to remember about detox mouthwashes:

They are most effective for about 20-30 minutes after use, and their effects may last a few hours. You’ll need to plan carefully when to use them. Make sure to follow all the instructions to get the desired results.

While a detox mouthwash can clean your mouth temporarily, it can’t stop your salivary glands from working or produce clean saliva.

Over time, the mouthwash will dissolve, and your mouth will fill up with contaminated saliva again. So, the key is to repeat the application multiple times.

Why doesn’t THC stay in saliva for very long?

THC metabolites are fat-soluble and are stored in body fat tissues. Since there are no fat reserves in the mouth, there’s nothing to keep THC in your saliva for long.

The presence of THC in swab tests comes from smoke that coats the mouth’s inner surface, allowing THC to be collected by swabbing the cheek.

Can CBD make you fail this test?

No. CBD is not psychoactive, so it isn’t tested in drug tests designed to detect marijuana use. Since only THC is checked in these tests, CBD alone won’t cause a positive result.

This means you can use pure CBD without worrying about failing a saliva drug test. However, the cannabis strains from which CBD is extracted often contain small amounts of THC.

Using concentrated CBD oil in large amounts can, in theory, result in a positive THC test.

To minimize this risk, consider using a detox mouthwash after using such products.

What is a mouth swab drug test, and why is it done

A mouth swab drug test, also known as the oral fluids test or saliva drug test, is a screening test used to assess substance use. A typical cotton swab is brushed on the inside of your cheek to collect a saliva sample, and you’re good to go.

These tests are generally used as a replacement for urine drug tests, and this is because they’re

a) straightforward and quick to administer and

b) collected right in front of the person conducting the test, so there’s a pretty slim chance of foul play.

Mouth swab drug tests are commonly used during pre-employment screening, period or random testing, and also after something suspicious might have happened at the workplace, i.e., related to drug use.

Certain police forces also use this test for roadside drug testing if they think a person could be driving under the influence.

What do mouth swab drug tests look for

Unlike urine tests, which look for the active metabolite THC-COOH, oral swab tests detect THC itself. This makes this test more reliable and efficient since THC remains in saliva for at least 24 hours before being metabolized by the body.

Here are the details of the detectable drugs, their cutoff levels, and their approximate detection times.

Generally, the detection window for oral fluids is 5-48 hours, but this window can be longer for regular and long-time users.

How long does a mouth swab drug test go back?

Drugs mostly become detectable in oral fluids within around 30 minutes of consumption, which is way faster than other tests.

This shorter time frame makes the mouth swab tests particularly effective for screening after accidents or in suspicious situations.

However, these are just generalizations. How long a swab drug test can detect a substance typically depends on the:

• the sensitivity of the test – some tests can detect substances for longer periods
• type of substance being detected – every drug is metabolized differently by the body and hence has its own detection window
• the dose of substance taken – the heavier the dose, the longer it stays in the system and can be detected
• body’s metabolism and how fast it can remove toxins from the body; faster metabolism means less detection time
• body mass; more body mass means a slower metabolic rate, which means a longer detection time
• age; older individuals have a slower metabolism
• hydration; more water consumed, more THC toxin flushed from the body via urine
• drug tolerance; a higher tolerance to drugs means a shorter detection time

Limitations in Oral Drug Testing

The most significant disadvantage of a swab drug test is when these drugs and their metabolites remain present in saliva.

As you may have noticed from the table above, the detection windows for drugs are far shorter than other methods – only a few hours to days, unlike weeks and months for urine tests.

This means that a person can stop using for a few days, test clean, and start using again!

Another limitation of swab drug tests is that certain medications can potentially interfere with and lead to inconclusive results. For instance, cough medicines containing codeine could impact the outcome of an opiate test.

And thirdly, unlike urine and blood tests that detect a large variety of drugs, some drugs cannot be identified in the saliva at all, which leads to limited testing prospects.

Which Employers Use Mouth Swab Drug Tests

To answer the questions of those looking for a job, any employer wanting to make sure a prospective candidate hasn’t been using drugs or isn’t using drugs while on the job can conduct a swab drug test.

This can mean educational institutions, jobs that require working with heavy machinery, and jobs that involve driving. Most federal positions require drug testing, and industries such as transportation, aviation, and defense are required to test applicants and employees for substance use.

When do employers use mouth swab drug test

There are many common occasions where employers would want to conduct mouth swab drug tests. These include the following:

• pre-employment tests are conducted right after you’re offered a job and are part of the overall employment screening process, including other background checks.
• Before a promotion – the offer of promotion could depend significantly on whether you pass the test.
• Random drug tests – employers may select a group of employees to take a swab test randomly. There is generally little advance notice for these types of tests, but employers need to inform employees beforehand that such tests could be conducted while they’re on the job.
• For-cause drug tests – if an employer, due to any valid reason, suspects an employee to be under the influence, they can ask the employee to submit an oral drug test.
• After an on-the-job injury or accident – this can include a driving accident or a mishap involving machinery. These tests can help the employer determine who and what was responsible.

Here are the results of the survey among the drug tested persons:

Question: I found the oral fluid swab test procedure more or less uncomfortable than the urine test

Results:

Do I have to take a mouth swab drug test?

The good news is that your employer cannot force you, or a potential job candidate, to take a mouth swab drug test.

But the bad news is that there can be negative consequences if you refuse to take the test.

Refusing to take a pre-employment oral drug test means that the employer can withdraw the job offer. Refusing to take a drug test while on the job could cause your company to fire or suspend you or refuse a possible promotion.

To avoid any confusion, it’s always a good idea to enquire about your company’s drug testing policy. You can ask someone from human resources for more information regarding these matters.

How a mouth swab test is conducted

The mouth swab drug test is the least invasive type of drug test; no poking needles or peeing in a cup.

Plus, these tests don’t require much preparation at all! You’ll only be asked not to eat or drink anything for at least 10 minutes before the test.

A mouth swab drug test is done using these basic steps:

1. A collection stick – a typical cotton swab with an absorbent pad or sponge on one end – is used to scrub the inside of the cheek gently.
2. The sample is enclosed in an air-tight sterilized bottle or container and sent for analysis, either on-site or in a lab.

What is an inconclusive saliva test?

An inconclusive test means that the results could not conclusively determine that a person was using drugs. Many factors could cause this, such as:

• the kind of test used
• the type of drug tested and its concentration
• the abilities of the person performing the test
• whether the time of testing was within the detection window for the specified drug
• quality of the testing device

If you believe your test results are inaccurate, you can take another test or have the test results reviewed.

Frequently Asked Questions (FAQs)

Q. How to produce saliva fast enough for the mouth swab device?

Certain drug-testing devices are flavored to stimulate the flow of saliva without hampering test results. Similarly, certain kits come with a minty tip for people who cannot produce enough saliva quickly.

Q. How far back does an oral fluid drug test go?

A mouth swab can assess whether someone has used drugs in a 3-24 hours window; hence these tests have the shortest detection window, which is extremely suitable for suspicion testing.

Q. Are oral drug tests accurate?

Oral fluid tests are highly reliable point-of-care tests (POCT), providing results in a matter of minutes.

Q. What are the benefits of mouth swab drug testing over urine testing?

• Mouth swab drug tests screen for recent substance use by detecting active metabolites, compared to urine tests that measure only by-product metabolites.
• Drug detection times for saliva test kits are shorter – between 6 hours to 3 days – compared to urine drug tests.
• Saliva test kits are user-friendly and non-invasive.
• They allow easy supervised specimen collection with virtually no chances of cheating.
• Saliva tests are great for employers to enable systematic drug check-ups ranging from pre-employment to post-incident.

Q. What does it mean when a mouth swab drug test turns blue?

The sample adequacy window of the saliva drug test turns blue when the sample quantity is adequate for testing. This reduces the need to do any guesswork while collecting oral fluid specimens and reduces the need to repeat collections.

Q. How do you know that you failed the mouth swab test?

Swab tests are straightforward to interpret. Negative and positive test results are displayed as colored lines on the drug panel of the test kit.

Q. What should you do after you failed to pass a mouth swab drug test?

There is nothing much that you can do after a confirmatory test comes back positive.

However, don’t just give in, especially if there is a lot at stake.

You might consider fighting back- but in a calm way.

We’ve heard cases of people who tested positive for drugs they had never used before.

This could be you. Act very surprised and claim that something must have gone horribly wrong.

Let them believe that there must have been a mistake somewhere and insist on taking a urine test instead.

If you are lucky to redo a urine test, then do everything possible to piss clean.

The convenient and guaranteed solution to pass mouth swab drug test

Stinger Detox Mouthwash

• Removes alcohol, nicotine, marijuana (THC), cocaine (COC), amphetamines, methamphetamines, opiates, etc.
• Works in 2 minutes
• The effects last for 30 minutes.
• Alcohol-free
• FDA registered & USA made
• Legal
• Not detectable
• Small and discreet

GET THIS MOUTHWASH