How to Use Saliva Drug Testing Kits to Detect Cannabis

Understanding Saliva Drug Tests for Cannabis

Detecting cannabis use has never been so easy! The smoke in a cannabis spliff is full of a molecule known as Δ9-THC, and a saliva drug testing kit detects this molecule in the mouth of the cannabis user. When smoking cannabis, the oral cavity is contaminated by the smoke, and this trail can last for several hours.

There Are Certain Limitations to Saliva Drug Testing

Depending on the person and the test, cannabis use can typically be detected for up to 6 hours. A saliva test detects THC, which is the active substance in marijuana. However, detecting cannabis using a saliva test can provide unpredictable results, particularly if the donor has drunk, eaten, or somehow removed THC residue from their mouth; or if the sample has not been properly collected. It’s important that collectors are aware of these aspects of drug testing when interpreting results. When a saliva test shows negative, it doesn’t necessarily mean that cannabis has not been used; it simply means there is no residual THC remaining in the oral cavity.

The difference Between Δ9-THC and THC-COOH?

  • In its raw state the cannabis molecule is known as Δ9-THC (Delta 9 THC). This is the actual cannabis substance located in marijuana (grass) and hashish (cannabis resin).
  • The molecule of cannabis that’s been converted by the body is known as THC-COOH (or 11-nor-Δ9-THC-COOH). In order for the body to eliminate the Δ9-THC it must be changed. This change results in THC-COOH, which can be found in urine in large quantities.

Comparing Urine and Saliva Drug Tests for Cannabis

In reality, these two tests can’t be compared because they don’t answer the same question. If the question being asked is: “Does this person use drugs?”, then a urine test is appropriate because it allows for background screening, enabling the detection of cannabis use over a period of days or even weeks. However, if the question being asked is: “Has this person smoked marijuana over the last 4 to 6-hour period, or any other drug over the last 24 to 48-hour period?”, then a saliva test can tell if that person has recently used a drug. It can’t detect if that person uses drugs on a regular basis because it screens on a relatively short detection time period.

More and More Companies Are Using Saliva Drug Test Kits

Increasingly, companies are using saliva tests in order to reduce the risk of accidents related to drug use because, ultimately, a company needs to know if a person has been smoking marijuana whilst at their workplace (perhaps during their break), which can signify a very real danger to other employees, colleagues, and the general public.

Saliva drug testing for cannabis can only detect the active THC drug compound prior to it being metabolised by the body. This means that a saliva drug test can only return a positive result if that parent drug remains in the saliva and mouth. And, as mentioned above, a saliva test for cannabis can be affected by the actions of the cannabis user, because the THC can be completely removed if the oral cavity has been effectively rinsed or cleaned.

This means that saliva drug testing for cannabis should be done without prior notice being given, and that the saliva sample should be collected for screening as soon as possible after the drug has been smoked. There is a window of between 8 and 12 hours to detect drug use using a saliva drug test, however this time period is still dependent on whether the oral cavity has been cleaned after smoking marijuana.

The Most Effective Way of Using a Saliva Drug Test to Detect Cannabis Use

In order to maximise the chances of detecting cannabis use, the sponge swab must be moved around the mouth, under the tongue, into the cheeks, and in front of both the top and bottom teeth. Thorough swabbing will increase the chances of obtaining THC in the saliva sample.

The Importance of Evaluating the Performance of a Saliva Test

Some saliva tests on the market today are completely ineffective because they’re designed to mainly track THC-COOH and not the Δ9-THC. As we now know, the only molecule remaining in the mouth after smoking marijuana is Δ9-THC. Only drug tests that can detect the Δ9-THC molecule will be effective.

Ideal Uses for Detecting Cannabis with a Saliva Drug Test

Saliva drug tests are an ideal drug testing tool for workplace screening, because a positive result indicates recent drug use. These drug testing kits are also ideal for medical and forensics screening. When used for roadside drug testing, a positive saliva drug test indicates that THC has recently been smoked; however, the test will probably miss any cannabis smoked prior to the mouth being rinsed or washed.

Best Saliva Drug Testing Kits for Cannabis

3 in 1 Saliva Drug Test (Oral Fluid Testing Kits)

3 in 1 Saliva Drug Test (Oral Fluid Testing Kits)

3 in 1 Saliva Drug Test Tests for the 3 most commonly abused drugs Cannabis, Cocaine and Heroin Simply put test under the tongue All-in-one test - nothing else needed! Results in minutes ... Read More

Add to cart

Photo by Anthony Cunningham for Zoom Testing

Zoom Testing is a leading UK drug testing company and a supplier of Drug Test Kits.

This post was originally published in January 2015 and has been updated since.

You May Also Like: