Oral Drug Test

An oral fluid drug test (also a mouth swab test or oral tox test) checks for drugs or alcohol in your body by testing a sample of your saliva (or spit). This test can detect a variety of drugs and substances like alcohol, marijuana, opioids and much more.

How does an oral drug test work?

An oral drug test involves using a cotton swab to collect saliva from the inside of your cheeks and gums. The test looks for specific drugs or their metabolites (byproducts) in your saliva. You can’t eat or drink for at least 10 minutes before saliva collection.

Once the swab is soaked with saliva, it’s removed from your mouth. The sample can be either tested immediately in a handheld device or placed in a collection tube and sent to a laboratory for analysis.

Point of collection tests can give results within minutes. Often, the sample is sent to a lab to confirm the result. Laboratory results are usually more accurate, but results take a day or two to get back. “At-home” test kits are also available, which you can do yourself.

What drugs can be detected in oral drug tests?

Some of the most common substances that this test detects are:

• Alcohol
• Amphetamines
• Cocaine
• Ecstasy
• Marijuana (cannabis, THC)
• Methamphetamine
• Opioids
• Roofies (rohypnol)

When would I need this test?

You might need an oral drug test for several reasons, like:

• For employment purposes
• To monitor people in substance use disorder treatment programs
• To see if a driver is under the influence (roadside testing)

What are advantages and disadvantages?

The advantages of an oral drug test are:

• They’re easy to collect (don’t need to draw blood or get a urine sample)
• The results come back fast
• They’re harder to tamper with
• They can detect same-day use

The drawbacks are:

• Accuracy varies (can miss low levels or certain substances)
• A shorter detection window (compared to hair or urine samples, which detect the substance longer)
• Often, they still need laboratory confirmation
• There can be false positives

How accurate are oral drug test results?

The best oral fluid drug tests can be around 97% accurate. The exact accuracy depends on the type of test (roadside or lab) and the substance being tested for. For example, many studies show that cannabis (or THC) is harder to detect in saliva. But drugs like cocaine and opioids are easier to detect.

Other factors that can affect the accuracy of your results:

• When you last took the substance
• How quickly or slowly your body breaks down the substance
• How often you take the substance
• The sensitivity and quality of the test itself
• Food/drinks in your saliva that can alter results

These tests don’t measure the amount of the substance; they just show that the substance is present. More advanced testing can identify the exact substance and the amount. If you know the test has falsely detected a substance in your sample, you can challenge the result. You can insist on lab-based confirmation and/or testing of a second sample.

How long can drugs be detected in saliva?

You can test positive for a few hours to a few days, depending on the drug and how much you took. Here are some common drugs and how long they’re detected:

*These are estimates. Several factors can determine exactly how long you’ll test positive.