Can You Fail A Drug Test Using CBD or Topicals?

Philip Ghezelbash August 3, 2019 0 comments

How to pass a drug test? Can CBD make you fail? What about topicals? Here’s the latest research.

Cannabis reform is spreading across the United States, with 33 states now legalizing some form of cannabis. But with the growing support comes the backlash. Cannabis tests are still common requirements for many jobs, athletes, and institutions. So, the question among patients is how to pass a drug test. For those who are legally consuming the plant for a medical condition, these tests can seem outdated and discriminatory.

Fortunately, cannabis testing is a lot less efficient than alcohol breathalyzer testing. It can involve urine, hair, saliva, blood, or even brain waves. The most well-known and common of these tests, however, is the urine test.

The IA Urine Test

IA urine tests give qualitative results. This means that it determines if cannabis is detected or not but cannot evaluate the amount present in the sample. IA is a cheaper, faster, and more convenient test than GC-MS. As such, it is the most common technique used in home drug test kits and point of care tests. 

This test has a high sensitivity to cannabis. However, other compounds that for which the device is not testing not may bind to the assay and result in a false positive. 

[bsa_pro_ad_space id=25]

IA tests work by recognizing the binding of an antigen from the substance being tested for (e.g. THC-COOH) to an antibody. If an antigen is present, it will bind to its antibody, causing a reaction and a positive result. 

THC-COOH, the main metabolite of THC, is the most common THC compound that is identified in cannabis urine tests. The amount of THC-COOH in urine needed to trigger a positive result in an IA test is 50ng/ml

how to pass a drug test

How to Pass a Drug Test Like The GC-MS

Gas Chromatography-Mass Spectromatry, or GC-MS, on the other hand, does provide a quantitative result. In other words, it can determine the level of cannabis metabolite present in the sample. Lab techs can use GC-MS to hypothesize the level of cannabis that the patient consumed. 

[bsa_pro_ad_space id=26]

GC-MS is typically used as a secondary test to IA. So if a sample returns a positive result for cannabis, GC-MS can then either confirm or negate the first IA result. This test separates the compounds in the urine sample by size. A device called a mass selective detector then identifies and measures the compounds. 

The amount of THC-COOH in urine needed to trigger a positive result in a GC-MS test is 15 ng/ml.

Ways To Fail A Urine Test

Due to the nature of both IA and GC-MS testing, the main reason for failing a cannabis urine test is the consumption of THC products. 

A sample would need 50ng/ml of THC-COOH to fail the first step cannabis urine test. So, you don’t have to be completely cannabis/THC free – you just need low levels to pass. 

One common question is “how long after THC consumption will THC-COOH be below 50ng/ml?” But it’s a tricky question to answer. Different people metabolize THC at different rates, so an exact time period is hard to nail down. But a range of 3 to 30 days is possible, depending on the frequency of consumption. 

Can CBD Products Result In A Failed Test?

Since the tests aren’t looking for CBD, urine containing only CBD and its metabolites will not trigger either an IA or GC-MS test. 

However, research has shown that some CBD products contain trace amounts of THC. If present in high enough doses, those traces will trigger a positive result for THC in both IA and GC-MS tests.  

In this case, GC-MS testing would possibly be able to determine if the rate of THC-COOH is rising or falling, and therefore suggest if the patient tested regularly actually consumes THC.

What About Topical THC?

With the rise of topical cannabinoid products, like lotions and salves to target specific areas, there is a new concern for patients asking how to pass a drug test. But can the use of THC topical products result in a positive urine test?

The research thinks not. 

One study found that when THC topicals were applied to the skin, all urine samples taken from participants returned negative THC results. Researchers took these urine samples every 2-4 hours until 15 hours after the first application of the THC topical. 

CBD cream with cannabis leaf

How To Pass a Drug Test

The best answer for how to pass a drug test is to avoid all products containing THC. 

As well as advertised THC products this also means CBD products that aren’t isolated CBD, as some of the more general CBD products may contain trace amounts of the psychoactive cannabinoid. If you are taking CBD products it’s also advisable to research whether manufacturers CBD used a process that could risk cross-contamination from THC. 

It’s also important to remember that exposure to secondhand cannabis smoke could result in THC metabolites in urine. One study demonstrated that THC is able to show up in blood samples of individuals exposed to secondhand smoke. Though, these were levels undetectable by either IA or GC-MS testing, with THC-COOH levels only registering at 7.8ng/ml maximum. 

If passing a cannabis urine test is of great concern to you, then the best solution is to stick to CBD isolates. Unfortunately, with the growing efficacy of these tests, and continued backlash, that’s the only way to keep your job safe. In the meantime, we need to urge lawmakers to change outdated employment regulations to match the growing wave of cannabis acceptance. Hopefully one day these tests will be a thing of the past.

Author avatar

Philip Ghezelbash

https://writingstudio.co.nz/
Philip Ghezelbash is an ex-personal trainer with a science background who currently operates New Zealand's only health specialized writing studio. He is passionate about presenting complex science in an easy to digest manner and is a firm believer that cannabis has substantial potential to be used as a medicine for degenerative disease.