What is a Mouth Swab Drug Test?

Mouth swab drug test detect marijuana, alcohol, opioids and other drugs.
Image by Melissa Ling. © The Balance 2019

When you are applying for jobs, you may be concerned about being tested for drug or alcohol use. Employers in some industries are legally required to drug test certain job applicants and employees. Many other employers require drug testing from applicants or employees, and there are different forms of drug testing available for this purpose. There are breath alcohol tests, blood tests for drugs and alcohol, urine drug and alcohol tests, and even hair drug tests.

One common type is a mouth swab drug test. Read on for more information on what a mouth swab drug test is, and how you can respond to your employer when asked to take this test.

What Is a Mouth Swab Drug Test?

A mouth swab drug test, also known as a saliva test or oral fluids test, collects saliva from inside the person's mouth, whether it's a job applicant or an employee.

The saliva is tested for the use of illegal drugs; typically, these tests can detect drugs used within the past few days. (However, some drugs stay in the user’s system longer than others.) Saliva can be tested for alcohol, marijuana, cocaine, amphetamines, and methamphetamines.

Mouth swab drug tests are popular for many employers, in part because they are less expensive than other drug tests. They are also easy to administer. Saliva is easy to collect and test, so this is the simplest and least invasive type of drug testing. Often, the tests can be done on-site, which makes them quick and efficient.

What Drugs Will Be Detected?

The drugs that can be detected by a mouth swab drug test depend on the test that is administered. Some tests check for more substances than others but, employers commonly check for marijuana, cocaine, opioids, amphetamine, methamphetamine, and PCP. Most tests can detect marijuana for 24 to 72 hours; opioids, for 24 to 36 hours; amphetamine, for one to five days; cocaine, for one to 10 days; methamphetamine, for one to four days; and alcohol, for one to five days.

Which Employers Use Mouth Swab Drug Tests?

A variety of companies use oral drug tests. Some companies have a testing policy that explains how and when applicants and employees may be tested for illegal drug use.

Some industries, including transportation and safety, may be required by law to test employees. Many federal positions, for example, require drug testing.

When Do Employers Use Mouth Swab Drug Tests?

There are a few common times that employers conduct mouth swab drug tests. Sometimes, these are pre-employment tests, meaning they are done right after you are offered the job. This drug test will be part of the larger employment screening process, which might involve various other background checks.

Oral drug tests may also be conducted before a promotion. Your offer of the promotion might be contingent on whether you pass the test.

Some companies conduct random oral drug tests, in which they select a pool of employees to take the test. Typically, there is little advance notice for these drug tests. However, the employer generally has to inform employees (typically in an employee handbook) that random drug tests are possible. Some states have rules about how far in advance employees need to be notified about tests.

Other companies conduct for-cause drug tests. In this case, if an employer thinks an employee may be under the influence of drugs (due to regular absences, lateness, poor performance, etc.), they can require the employee to submit an oral drug test.

Finally, some employers conduct these tests after an on-the-job accident or injury. This might include a car accident, or an accident involving operating machinery. These drug tests help the employer decide who is liable for the accident.

Do I Have to Take a Mouth Swab Drug Test?

An employer cannot force an employee or job candidate to take an oral drug test. However, there will likely be negative consequences for refusing a test. If you refuse to take a pre-employment oral drug test, an employer can revoke a job offer. If you refuse to take a drug test while you are a current employee, your company can fire or suspend you, or refuse you a promotion.

If you take an oral test but believe the results are inaccurate, you may be able to have another test or have the specimen reviewed again. Check with your company for information on how you can request a retest.

You can ask your company about its drug testing policy as well. Typically, the policy should be clearly laid out in an employee handbook. If this is not the case, you can talk to someone in human resources for more information on company policies.

Federal and State Drug Testing Laws

Finally, policies regarding drug testing vary from state to state. For example, some states have limits as to when and how drug screening can be conducted, and others have restrictions on what circumstances can prompt employers to test for drug or alcohol use. Look up your state’s policy if you are unsure.

Federal laws such as the Drug-free Workplace Act of 1988 are designed to target workplace substance use. They legally require some employers to take action against drug use in the workplace, such as by developing a written policy. Some industries, including transportation, defense, and aviation, are required to test some applicants and employees for drug use.