Last updated : March 31, 2025
The mouth swab drug test is an effective and convenient way for Minneapolis employers to combat the well-known fact that drug abuse is one of the nation’s most pressing problems, affecting nearly every area of the country.
Minnesota is no exception. A recent study found that Hennepin County, which includes Minneapolis, the state’s largest city, experienced a significant year-to-year increase in opiate and cocaine-related deaths. The amount of meth seized by Minnesota police in recent years has increased 500% from a 2009 low. With drug use on the rise, and the negative impact of such drug use on workplace performance extensively documented, many employers in Minneapolis are evaluating their need for drug testing services.
While employers have several testing options to choose from, mouth swab drug tests, also known as an oral fluid or saliva drug test, are gaining popularity largely because of the ease with which they can be administered. A mouth swab test, which is performed by placing a sterile swab in the subject’s mouth to collect a small amount of saliva that can then be tested for any number of substances, is less invasive and time-consuming than a blood or urine test.
Another benefit lies in the fact that it can be conducted right on the job site, in view of the tester, making it far less vulnerable to cheating or tampering than a urine test. In addition, although mouth swab drug tests cannot detect drug uses for as long after ingestion as urine or hair follicle drug tests, they can detect these substances more quickly. This makes them more effective at catching very recent drug use than the other tests. In fact, several law enforcement agencies throughout the country are using, or are considering using, mouth swab tests to identify people who are driving while impaired by drugs like marijuana. The primary disadvantage of mouth swab tests is that they are not currently approved for DOT drug testing, though pending legislation may change that soon.
How does a mouth swab drug test work?
Mouth swab drug tests analyze saliva for parent drugs and their metabolites, which are the byproducts of the human body processing drugs that have been ingested. Any drug that is ingested is metabolized by the body and excreted as metabolites in bodily fluids like saliva. While there are commercial adulterants available on the market, research shows that most of them do not significantly alter the concentration of drugs in saliva. The same is true of common mouthwash products. Even substances that may have altering or diluting effects on saliva will not exert those effects for long; since fluid in the mouth is quickly turned over, a wait of several minutes will allow a re-equilibration of drugs in surrounding mouth tissues.
When to use mouth swab drug tests
Mouth swab drug tests are so convenient they are suitable for almost any situation, including pre-employment and return-to-duty testing. They are particularly useful in the context of post-accident or reasonable suspicion scenarios. The speed and efficiency with which they can be carried out, along with the fact they can detect drugs within minutes of ingestion and can be performed anywhere while the employer observes, makes them ideal for testing employees involved in workplace accidents immediately after such accidents occur. Similarly, a mouth swab test is the best method to use when an employer wants to quickly test an employee who is exhibiting signs or symptoms of being under the influence of drugs while at work. They are also extremely handy for random drug testing, but employers in Minneapolis, and Minnesota in general, should be aware that Minnesota permits random testing only when an employee holds a safety-sensitive position in which an impairment caused by drug or alcohol usage would threaten the safety or health of another person, or when the employee is a professional athlete subject to a collective bargaining agreement that allows random testing.
How to conduct a mouth swab drug test
Specific steps will vary slightly depending on the test brand, but the following are generally applicable:
Step 1: Prior to fluid collection, instruct employee to empty mouth of any food or other objects. Employee should rinse his or her mouth with water, and employer should then wait a minimum of 10 minutes before collecting a specimen.
Step 2: Instruct employee to pool saliva in mouth briefly before collection.
Step 3: Instruct employee to insert the swab into his or her mouth and place the absorbent pad between the lower cheek and gum, directing saliva onto the pad.
Step 4: Employee should leave swab in mouth, without chewing or sucking on it, for several minutes while the pad absorbs a sufficient amount of fluid.
Step 5: Instruct employee to remove swab from mouth and then guide swab into secure collection tube.
Step 6: Complete the necessary chain of custody procedures by following specific test instructions and using tamper-evident seals on the specimen.
Step 7: Ship specimen to testing laboratory.
Step 8: Receive results from laboratory.
Drugs that can be identified
These tests can accurately detect the following drugs:
- Cocaine
- Opiates/opioids
- Marijuana
- Synthetic marijuana
- Ecstasy (MDMA)
- Methamphetamine
- PCP
- GHB
- Rohyphnol (roofies)
- Benzodiazepines
Detection windows
A mouth swab drug test has a very short detection window, making this kind of test excellent for identifying very recent drug use. The following are some general detection time frames:
- Cocaine: 1-48 hours
- Opiates / opioids: 1-36 hours
- Marijuana: 1-24 hours
- Methamphetamine: 1-48 hours
- Alcohol: 1-24 hours