How To Use Hydrogen Peroxide To Pass a Mouth Swab Drug Test

Daniel Miller
By Daniel Miller

Ph.D Pharmacology, Drug Testing Specialist

Updated: 2022 May 11

Hydrogen peroxide has been promoted as a solution for passing a mouth swab drug test.

Does it work? Yes.

Scientific studies confirm that hydrogen peroxide can lower the THC levels in your saliva to undetectable amounts.

However, studies also indicate that water has a similar effect.

Given the potential side effects of excessive hydrogen peroxide use, I would recommend opting for water instead.

Here’s a guide on how to pass a mouth swab drug test using peroxide, along with the scientific explanation for its effectiveness.

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How to pass a mouth swab drug test with peroxide: Instructions

After you use marijuana, millions of THC molecules coat the inside of your mouth. The goal is to remove these molecules quickly.

First, avoid using cannabis for at least 48 hours before your test. THC can be detected in your saliva for 24 to 48 hours, so staying clear of marijuana improves your chances of passing, especially if you’re a heavy user.

Next, brush your teeth several times before the test. This helps keep the fluids in your mouth moving and removes THC from the surfaces inside your mouth.

  • Just before your test, rinse your mouth with hydrogen peroxide.
  • Take a sip of peroxide, swish it around in your mouth for 30 seconds, and then spit it out.
  • Be careful not to swallow any peroxide as it can be harmful if ingested.
  • Repeat this rinse 3-4 times to help reduce the THC levels in your mouth to below detectable levels.

Now, I’ll explain why this method works.

How mouth swab drug tests detect marijuana

A mouth swab drug test detects delta-9 THC, the psychoactive compound that gets you high.

A single cannabis joint contains millions of delta-9 THC molecules.

This compound is heavily present in the saliva almost immediately after consuming marijuana or hashish because it coats the entire surface of your mouth, which is why it shows up on the swab test.

This is what makes it difficult to pass a surprise saliva drug test, especially if you’ve smoked marijuana a few hours earlier.

Most drug testing companies currently use a cut-off of 25ng/ml when testing for marijuana use in saliva.

How long is THC detectable in the saliva?

THC in saliva concentration chart

The good news for you is that THC does not stay for so long in your mouth. A study published on researchgate.net aimed at investigating how long THC takes in the saliva in the controlled administration of smoked cannabis.

In this experiment, the first specimen collected from one of the subjects showed a THC concentration of 5800ng/ml using a GC-MS test 12 minutes after smoking.

At around the 20th minute, another experiment was done and showed that the concentration had fallen to 81ng/ml. 12 hours later, the concentration had declined to below 1ng/ml.

While the study above shows that the THC concentration in the saliva had fallen way below the detectable level within 12 hours, it’s worth noting that most saliva tests that the labs use today can detect marijuana in your saliva 48 hours after firing up a joint.

Therefore, if you want to skirt through the test, it pays to keep off weed for at least 48 hours (72 hours would be much better) to the test.

Can the THC metabolites in your system be diffused back into the saliva?

I understand that heavy and long-term smokers often worry about THC moving from their bloodstream back into their saliva, even after not smoking for up to 72 hours.

Studies have found that THC gets trapped in the cavities right after you use it. Luckily, over time, the amount of THC decreases as it gets absorbed into your bloodstream.

Furthermore, there isn’t much research on this, but it seems clear that THC does not move back into the saliva once it enters the bloodstream. Researchers analyzing drugs in saliva for the Federal Office of Road Safety observed that THC is very lipophilic, meaning it doesn’t easily return to the saliva after it has entered the blood.

This is why someone who uses cannabis might fail a blood or urine test but pass a saliva test if they haven’t used cannabis in the last 48 hours.

Does hydrogen peroxide help pass a saliva drug test? Here’s the scientific evidence.

A 2014 study published in the Journal of National Institutes of Health aimed to assess the effects of different mouthwashes on cannabis oral fluid concentrations.

I’ll explain how this study explored the effectiveness of various substances, like water, whole milk, and a hygiene product named Kleaner, in reducing THC levels in saliva. This is crucial for drivers, as many places check a driver’s saliva for drug use.

The study spanned four days and involved 11 regular cannabis users who smoked their usual amount each day. Researchers collected saliva samples multiple times each day, before and after smoking, to measure THC levels.

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

Results indicated that rinsing with water significantly lowered THC levels immediately after rinsing. However, the THC levels post-smoking were still well above the police threshold for drivers. This means to effectively reduce THC to undetectable levels, multiple rinses are necessary.

From the study, it appears that any mouthwash can help reduce THC levels. You could use hydrogen peroxide or water, with water being the safer option.

Conclusion

Hydrogen peroxide can indeed save the day if you are warned about an oncoming saliva drug test.

However, as the study above proves, water yields the same results.

Therefore, if you don’t want to subject your gums and tongue to the stinging effect of hydrogen peroxide, water is a good way to go.

Besides, water will also save you some bucks.

Frequently Asked Questions

How long should I avoid cannabis ahead of a saliva drug test?

Time is always your best friend when faced with any drug test.

The 2014 study that we’ve just seen above clearly indicates that 15 minutes after consumption, the concentration of THC in the saliva samples was still significantly higher regardless of the type of mouthwash used.

This means that while rinsing and brushing your mouth helps to scrub most of the THC molecules that might be stuck on your mouth surface, direct absorption of THC through the oral cavity into the bloodstream also plays a huge role.

Therefore, the longer you abstain from the drug, the fewer the molecules that you’ll need to brush and rinse off.

Consequently, you’ll have up your chances of passing the saliva test.

Will hydrogen peroxide help when alerted to a saliva test due in less than 24 hours?

This might be a difficult situation to be in, and you’ll really need a lot of swishing, gargling, and brushing to game the results.

I’ve heard that eating a lot of fatty meals might also help minimize the concentration of THC molecules on the surface of your mouth.

While this is yet to be verified, it seems like it would work, keeping in mind that THC is extremely fat-soluble.

If you are in a tight position and need to pass that test, go ahead and add pizza and ice cream or any other fatty food that comes your way to your regimen.

Should I swallow the Hydrogen Peroxide solution when using this method?

Well, I’ve come across several sources that suggest that you should swish and swallow the hydrogen peroxide solution some minutes before the saliva sample is taken.

In my opinion, this isn’t necessary. It could be dangerous, especially in high concentrations.

When ingested in high amounts, the National Capital Poison Center says that hydrogen peroxide could trigger an episode of vomiting and a lot of stomach irritations.

Oral Clear Gum
  • Acts in 30 seconds
  • Most effective to pass a drug test
  • Lasts for 30 minutes
  • Legal
  • Price: $95
GET YOURS
Toxin Rid Mouthwash
  • Works in 6 minutes
  • Effective for up to 30 minutes
  • Legal
  • Price: $30
GET YOURS