Detection Time: Oral Fluid or Mouth Swab Drug Test

Table Of Contents:

• What are the substances detected?
• Testing procedures
• Oral fluid/Mouth swab detection time
• Oral fluid/ Mouth swab drug test limitations
• The takeaway

Oral fluid or mouth swab drug testing is a non-invasive drug testing method that works by testing an individual's saliva. A cotton mouth swab is rubbed on the inside of the cheek to collect the oral fluid specimen. The sample is then processed and analyzed in a lab for the presence of illicit drugs. Alternatively, the oral fluid specimen can be collected separately in oral drug testing kits that can be used on-site at the workplace or at home to screen for drugs with instant results.

Oral drug tests are increasingly gaining currency as a viable alternative to other standard drug tests such as urine and hair drug tests. The proposed 'Mandatory Guidelines for Federal Workplace Testing Programs using Oral Fluid, 'published by the Substance Abuse and Mental Health Services Administration (SAMHSA) in 2019, estimates 25 to 30 percent transition of all federal workplace drug testing to be conducted using oral fluid in the next four years.

Oral fluid or mouth swab drug tests are incredibly easy to carry out and difficult to tamper with. Adulteration, dilution, and substitution are common in the collection of specimens involving urine and other specimen types. On the other hand, an oral fluid specimen is collected under supervised observation, which negates the manipulation and distortion of test results.

What are the substances detected?

Oral drug tests have found applications in screening employees at the workplace for the most common drugs of abuse. Substances include alcohol, MMJ, cocaine, steroids such as amphetamines, methamphetamine,  barbiturates,  opioids and opiates like methadone, 6-MAM, morphine,  and hallucinogens such as phencyclidine.

Testing Procedures

Labs perform an initial oral drug screening to determine the levels of illicit substances present, giving either a negative or a presumptive positive result. Initial screenings are commonly performed using enzyme-linked immunosorbent assay (ELISA). Results of initial oral fluid or mouth swab tests are generally available within 24 hours. A confirmation test is required if the drugs analyzed are tested presumptive positive or above the initial screening cutoff level.

Confirmation testing is carried out to confirm a false positive drug screen or, in some cases, a false negative. Confirmation tests employ either "gas chromatography-mass spectrometry" (GC/MS) or "liquid chromatography-mass spectrometry" (LC/MS) to eliminate false positives or false negatives. Results for confirmation testing are available within 72 hours after the initial screening. Presented below is the official cutoff level for oral fluid in detecting common drugs of abuse, proposed by SAMHSA:

Oral Fluid/Mouth Swab Detection Time

Detection time for common drugs of abuse is longest in the hair, where they may be detectable for up to 90 days, followed by urine, where substances may be detectable for a week or more depending on the frequency of use. In contrast, drugs are detectable in oral fluid for up to 48 hrs and may be detectable in less than an hour of ingestion. This shorter detection window makes it particularly effective in detecting recent drug use.

Detection time involving mouth swab drug test depends on several factors such as the type of drugs used, dose, sensitivity of the testing method, preparation and the route of administration, duration of use, and concentration of the specimen analyzed.

Oral tests provide instant and timely results. Results of on-site testing outside laboratory environments are often ready within minutes of specimen collection and proven to be scientifically accurate. For this reason, Oral drug tests have found widespread application in testing employees at workplaces and, more recently, in roadside drug testing.

An oral drug test is easier to administer. It can occur on-site, which significantly reduces the time and cost involved in laboratory testing a given oral fluid sample. The time saved from workplace testing is estimated to be half of what it would typically take for administering the test.  The savings generated may be noteworthy, especially when this time is converted to an hourly wage.

Oral fluid/ Mouth Swab Drug Test Limitations

While oral drug tests offer many advantages compared to other drug screening methods, it has its own limitations. Its tighter drug detection window means it cannot detect illicit drug use beyond 48 hours. Here, the test subjects must be tested not long after drug ingestion. It is also difficult to measure the frequency of drug use because of this limited detection window.

The lack of sufficient training on the part of an on-site collector conducting the test or supervising the collection and improper handling of the collection device can hamper the result of an oral fluid/mouth swab drug test. Additionally, ingestion of certain over-the-counter (OTC) medication and other liquids and food knowingly or unknowingly can taint the result of an oral drug test. Test subjects have to be observed closely and ensure that they do not ingest anything at least 10 minutes before taking the test.

The takeaway

Invasive drug screening tests such as urine and blood are often hazardous and painful. They are unobserved and prone to contamination and adulteration. An oral fluid / mouth swab test occurs under supervised observation and significantly lessens the risk of substitution and adulteration. They are also easy to administer and boost productivity in the workplace by cutting down on cost and time.

Oral fluids have a short detection window of 5-48 hours. This narrow drug detection time in oral fluid makes it ideal for reasonable suspicion testing and post-incident testing. It has also found increasing application in roadside testing for alcohol and other common illicit substances. Results of on-site testing outside laboratory environments are timely, with accurate results within minutes of specimen collection. Laboratory-based oral fluid initial screening results are generally available within 24 hours, and confirmation test results of false positives are available within 72 hours from the initial drug test.