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How To Pass A Mouth Swab Drug Test

People try various methods to pass a mouth swab drug test, but so far there is no conclusive proof that any of them actually work.

How To Pass A Mouth Swab Drug Test

While many people swear that they passed a drug test with Listerine mouthwash, chewing gum, or a specialty detox product, their testimony can only be considered anecdotal reports. This isn’t to say that they aren’t telling the truth, only that there is no way to verify if the methods used are reliable.

How To Pass A Mouth Swab Drug Test

With that said, if you want to know how to pass a mouth swab drug test, we will explain the different theories in this article.

Listerine Mouthwash and Listerine Strips

Listerine Mouthwash and Listerine Strips

The Listerine mouthwash and Listerine strip method is probably the main method that you’ll see discussed if you run a quick search online.

This method is no use if you are faced with a spot check, but may help if you have a few days to prepare for your test. Listerine is only said to work to foil the marijuana part of the oral drug test.

Obviously, you will need to stop using marijuana as soon as you learn that you will need to take a drug test.

A big part of this method involves keeping your saliva production running as high as possible. The claim is that the more saliva you produce, the more it can cleanse THC metabolites from your oral tissues.

To increase saliva production, eat lots of high-moisture foods like fruits and vegetables, as well as spicy foods like hot peppers, and ginger.

Avoid drying foods like chips, pretzels, crackers, and nuts.

The other type of food that you should eat is fatty food. THC molecules have an affinity for fat, so the reasoning goes that by eating foods with a high-fat content, the THC and its metabolites still present in your mouth will attach to the fat and be removed.

Fatty foods include cheese, whole milk, meat, mayonnaise, and butter.

You could also try oil pulling to get the most from this part of the method. Oil pulling involves swishing cooking oil or coconut oil around in your mouth for about 5 minutes until it’s white and foamy. Then you should spit it out, don’t swallow.

During the days before your test, pay close attention to brushing your teeth and other oral surfaces. Use a softer toothbrush than you would ordinarily use, or you may make your mouth so sore that you can’t continue to cleanse. And using mouthwash on a sore mouth would be torture.

When you brush, you need to clean your tongue, your gums, and your inner cheeks as well as your teeth. Use plenty of toothpaste, and spit and rinse regularly. Aim to brush for 5 to 10 minutes, in the morning, afternoon, and before bed.

Each time you brush, thoroughly rinse your mouth with Listerine mouthwash. Swish it around in your mouth, hold it in your mouth, then swish it some more before you spit it out.

On the day of your test, before you leave home, go through a really long brushing session lasting 20 to 30 minutes. Rinse with Listerine, then begin to use Listerine strips.

Place Listerine strips inside your cheeks and under your tongue. As they dissolve, keep on replacing them.

When you arrive at the test center, rinse your mouth with water, then use more Listerine strips until you’re called in to give your sample.

They will normally ask you to wait under observation for 10 minutes prior to your saliva sample being taken. Use this time to generate as much saliva as you can to make your mouth as clean as possible.

Standard Chewing Gum

Chewing gum is a very common way that people try to beat the random drug tests that get sprung on them, leaving no time to go through the longer mouthwash and mouth brushing process.

As you might expect, the chewing gum method uses chewing gum. The flavor of the gum doesn’t matter and it won’t make any difference if the gum contains herbal extracts or normal synthetic flavors.

The way that chewing gum is claimed to work is that it stimulates saliva production. By chewing furiously on your way to get tested, you can build up a large amount of saliva which will help to cleanse drug metabolites from your mouth.

The more saliva you can generate and swallow, right before your test, so the theory goes, the fewer drug residues will be present and able to be picked up by the testing swab.

This method is only claimed to work for marijuana users and could possibly help you if you were a light user on the cusp of the 48-hour drug detection window. At the very least, it won’t make the situation any worse.

Specialty Detox Products

Detox chewing gum and detox mouthwash are two purpose-made products that claim to help you pass a mouth swab drug test. We’re not making any claims about these products, merely telling you how they are supposed to work. Let’s look at the detox chewing gum first.

Detox Chewing Gum

Unlike regular chewing gum, the chewing gum marketed for passing drug tests contains an active ingredient which is derived from hydrogen peroxide. This ingredient is called buffered perhydrol.

Here is how to detox gum is supposed to work.

Before your test, you discreetly pop the gum into your mouth and chew. As you chew, a teeny capsule containing the buffered perhydrol will break and release the liquid.

Don’t swallow the liquid. Instead, use your tongue to move the liquid around so that it coats your mouth. You need it to coat your cheeks, your tongue, underneath your tongue, your gums, and your teeth.

The drug test beating effect of buffered perhydrol is supposed to work within 30 seconds and last for 30 minutes. As long as your drug test is carried out within 30 minutes of using the gum, the proponents of these chewing gums say that you will beat the test.

One brand you can look at is Oral Clear. Be warned, though, that the gum is expensive and there is no guarantee that it will help you pass a mouth swab drug test.

Detox Mouthwash

The other type of product commonly used is a detox mouthwash. Again, there is plenty of hype about these products, and some people using them claim to have passed their saliva drug test soon after smoking marijuana.

However, a closer look at their claims shows that they had actually smoked the drug well outside the 48 hour window of detection and they simply didn’t know how long marijuana could be detected in a saliva test. So because they passed, they incorrectly assumed it was the detox product.

Other detox mouthwash users who smoked closer to the time of the test failed their test after using the mouthwash.

And users of cocaine and methamphetamine don’t seem to have had any success with this type of product.

The most popular mouthwash used by people facing a drug test is Stinger Detox Mouthwash.

To use a detox mouthwash, the makers claim that all you need to do is swish it around your mouth just before your test.

Given the lack of consistent results seen with these products, it would be unwise to pin your hopes on using these detox chewing gums and mouthwashes to pass a mouth swab drug test.

Interesting Article: Best Mouthwash For Swab Test

Take A DIY Drug Test At Home

If you’re preparing for job applications and interviews, you will ideally have time to stop taking drugs so that they are out of your system before you have to provide a saliva sample for your drug test.

But if you’re unable to successfully abstain from drugs, or your test has been scheduled sooner than you expected, you can take a test at home to find out if you will pass or not.

DIY saliva drug tests can be picked up from your local pharmacy or purchased from many online retailers.

If you get a positive result on your home test, the best course of action is to try and reschedule your actual test for 2 or 3 days later.

How Long Can A Mouth Swab Test Find Drugs In Saliva?

How Long Can A Mouth Swab Test Find Drugs In Saliva?

A mouth swab drug test usually takes the form of a 5-panel drug screen, which will test your saliva sample for the following commonly abused drugs.


Opiates include substances like heroin, morphine, and codeine. These drugs will generally be undetectable on a saliva test once 36 – 48 hours have passed since your last use. However, in some cases, morphine may still be present in a detectable form for up to 3 days.


Cocaine should be out of your system and undetectable using a mouth swab test 48 hours after your last use.


The standard window given for the detection of THC metabolites is 24 – 48 hours. However, this is based on light use, and if you are a regular, heavy user of marijuana, it would be sensible to abstain for longer prior to your test date.

Marijuana users with a higher body fat percentage will also need to stop using for a long time before their test because marijuana metabolites accumulate in fat tissue. And the more fat you have, the more THC metabolites your body can hold on to.

Take note – In states where marijuana is legal for recreational use, employers may still have zero tolerance for drug use. Your medical marijuana card may not prevent disciplinary action from being taken against you.

Amphetamines and Methamphetamine

These substances should be undetectable in saliva 48 hours after you last used the drug.

Phencyclidine (PCP)

Phencyclidine should be out of your system as far as your saliva is concerned 48 hours after your last use.

If your employer asks for an extended 10-panel drug screen, the additional substances tested for are:

  • Alcohol – detection window up to 12 hours for normal levels of use.
  • Methadone – detection period of 2 to 3 days.
  • Benzodiazepines – remains detectable for 5 to 10 days.
  • Oxycodone – detectable for up to 48 hours.
  • Buprenorphine-Suboxone – detection window up to 3 days.


As you can see, there is no clear and conclusive answer for how to pass a mouth swab drug test.

While many people claim that it’s easy to pass a saliva drug test with Listerine, chewing gum, or a drug detox formula, you really shouldn’t base your own decisions on reports from strangers online, or, for that matter, from people that you know. Dodgy advice is everywhere, as are people who have fallen foul of drug tests that they thought they could beat.

Because you don’t know other people’s drug use levels or the time frames involved between their last use and their test date, you can’t safely evaluate whether their method had any genuine effect on their test results. In all probability, any perceived effect was entirely coincidental.

The only way to be absolutely certain that you’ll pass your mouth swab drug test is to stop taking drugs in the period leading up to your test, then take an at-home test to make sure the drugs are out of your system. Reschedule your test to give yourself a longer detox period if you can.

Recommended: How Far Back Does A Mouth Swab Drug Test Go?