What exactly is a Mouth Swab Drug Test?

The oral swab drug test is a screening test used to detect drug use. It is also called an oral liquid drug test or saliva test.


To detect narcotics and alcohol, the oral swab drug screening uses saliva. Employers often use these assessments since they are convenient to conduct

Read on to learn more about saliva drug testing and its uses.


  • The oral swab drug screening uses secretion (saliva) for the identification of substances and drugs.
  • An oral swab test can detect the drug in saliva drug testing within 24 to 48 hours after ingestion and use.
  • The rules for drug testing vary by state and industry.
  • Employers use drug testing to screen applicants, make sure the workplace is drug-free, and determine responsibility for a workplace accident.

So, What Exactly is a Mouth Swab Drug Test?

The drug screen test for the oral swab gathers saliva from the inside of the mouth. The swab is then sent to a laboratory for examination. 

While rapid drug tests for oral swabs are commercially available, employers generally do not use these tests because SAMHSA‘s (Substance Abuse and Mental Health Services Administration) Mandatory Fluid Guidelines do not cover them.

Federal employers must abide by the law and the policy must also be abided by certain federal contractors.

 The alternate names of the tests are the Saliva test and Oral Fluid test.

How Does it Work?

Oral drug smear can detect medications used in recent days. Alcohol, tobacco, heroin, methamphetamines, and amphetamines can be screened through saliva.

Oral drug testing is common for workplace testing because it is inexpensive than other drug screening. It is also quick to gather and examine saliva, making it the most transparent and least intrusive drug screen. Typically, testing can be done on-site, thereby improving test performance and making the process less disruptive to work.

Several drugs can be detected by an oral swab drug test. Some of the tests might look more appropriate than the others. Still, employers generally screen for cannabis, cocaine, opioids, amphetamines, methamphetamine, and pentachlorophenol.

The oral swab test is used to assess current or recent drug use. They can usually detect the substance shortly after the service and within 24 to 48 hours after use.

The change of the substance detection window depends on the substance used, the frequency of use of the essence, and its amount.

Do Companies Have Testing Policies?

Oral drug tests are often used by companies. Some organizations have created drug testing policies that clarify when and how to evaluate candidates and staff for illegal substance use.

The law may require specific industries, including transportation and security, to test employees. Most federal positions require checking for illicit drug use.

The guidelines for checking drugs differ from country to country. For instance, some states have limits on how and when drug screening is conducted. 

In contrast, others have restrictions on the circumstances in which employers may be required to test for drugs or alcohol. Check the regulation of your government if you are not sure about your local laws.

Federal regulations are intended to fight drug abuse in the work environment, including the “Drug-Free Workplace Act of 1988.” 

Legally, they demand certain companies to take measures, including establishing a formal drug prevention policy for the organization. Specific industries, including transportation, defense, and aviation, need to evaluate drug use for individual applicants and employees.

When Do the Employers Conduct These Tests?

Employers often conduct drug tests for swabs. Sometimes these are pre-employment tests, which means they are done as soon as you accept a  job. This drug test will be part of a more extensive job selection process that may include other background checks.

You can also do oral drug testing before promotion. The promotional offers you offer may depend on whether or not you pass the test.

Some organizations are conducting random drug tests, from which a group of workers are chosen to undergo the tests.

Usually, these drug tests come with almost no warning. Employers generally must inform employees about the possibility of random drug testing.

The company can also conduct drug tests. Suppose an employer believes that the employee may be affected by the drug (due to frequent absenteeism, lateness, poor performance, or irrational decision-making). In that case, they may ask the employee to take an oral drug test.

Some employers also perform these tests after an accident or injury on the job. This can include traffic accidents or accidents related to the operation of machinery. These drug tests can help employers determine who is responsible for an accident.

An oral swab drug test can detect a drug faster than a urine test. Still, a urine test can detect the substance over a more extended period.

Do you have to Undergo Oral Swab Drug Testing?

Companies must not pressure employees or potential employees to perform random drug testing. Even then, the refusal of the test may have adverse implications. 

If you fail to take a pre-employment oral drug screen, your employer can remove your employment offer. If you fail to take a drug test when you are an employee, your company may fire you, detain you, or refuse your promotions.

If you are running an oral test, but the result is not accurate, you can run other tests or recheck your sample. Contact your company for information on how to request a new trial.

You may even ask the organization about its policies on drug tests. These guidelines can usually be explicitly outlined in the Employment Contract. If that is not the case, you should ask the HR Department for more details about the business policy.

How long do the Results Take?

The duration of the result depends on whether the sample is sent to the laboratory or analyzed on-site.

Laboratory results usually last 24 hours. Home drug test kits and field test equipment (including those used for road tests) provide results in minutes.

How Far Back Can it Detect Things?

It relies on several aspects: the quality of the sample used, the quality of the medicinal product used, and the volume of the test material used.

Some devices are more sensitive than others. Compared to other substances, you can detect some substances over a more extended period.

How long precisely an individual has been using a drug often influences the time of detection. Research shows that individuals who use the drug frequently have a higher chance of detection over a longer period of time.

Generally, the drug can be found in oral fluid 30 – 60 minutes after intake. This is a lot faster than the other measures. The short periods of this test make it particularly useful for detection after an accident or under reasonable suspicious circumstances. 

If you are still confused, check how long the drugs stay in your system.

The general window of detection for oral liquid is 5-48 hours. However, for people who use the substance frequently or for long periods, the window may be longer.

How Accurate is it?

If done correctly, the accuracy of most oral swab tests will be close to 98%.

However, there are a few factors that can affect accuracy, including:

  • The type of test used.
  • Drug type and concentration
  • The skills and abilities of testers and test subjects.
  • Whether the test was done within the detection range of the specific drug.
  • Test equipment quality

There are also differences in precision between laboratory tests and rapid tests. In general, immediate oral saliva test kits and kits are not as accurate as laboratory tests.

Limitations in Oral Drug Testing

While the oral test has many advantages, there are some important limitations to keep in mind. The most obvious drawback is the amount of time the drug or its metabolites are present in saliva. 

The test time interval is usually much shorter than other methods, which means that the user can easily use it for days, run a clean test, and reuse it. Additionally, drug use can affect the test result and lead to uncertain results.

For example, codeine-containing cough medicines can affect opioid test results. Some drugs cannot be identified at all in saliva, making testing for those drugs impossible.

Some people try to cheat on oral drug tests, usually by drinking lots of water, chewing gum, or using specially marketed products to alter the state of saliva. Check this out on how to pass a drug test.

However, these efforts often fail. To prevent food substances from interfering with the results, the subject is generally required to keep their mouth empty for at least 10 minutes before testing. So far, no useful substance has been found that has been proven to interfere with saliva.


Due to the test’s non-invasive nature, the oral swab examination offers exciting possibilities for a wide variety of drug, disease, and genetic testing applications. 

Because the process is more comfortable and less prone to errors, oral tests are gradually replacing other monitoring forms whenever possible.

The oral swab drug test has become a popular alternative to urine drug testing because it is easy to use, cost-effective, and samples are more challenging to handle.

The substance does not stay in the oral liquid for a long time. The procedure with a small detection window is, therefore, crucial to achieving correct data. In other terms, oral swab drug testing can measure swallowed drugs better than most other methods.