What’s the Difference Between a Drug Test and a Drug Screen?

Easily explained...

Even with the continued improvement of cannabis legalization around the country, drug testing and drug screening remain a pretty standardized practice across nearly all hiring organizations.

As such, it pays as a cannabis user when submitting your resume out to dozens of different companies, to know what to expect when that telephone rings and your potential employer asks you to come in for an interview – and later (hopefully), a drug test.

In this article, we point out the difference between a drug screen and a drug test, and highlight a few important things that are worth knowing about before you get yourself too worked up about having to go in to test for the presence of marijuana in your system.

The Difference Between a Drug Screen and a Drug Test… Could Cost You Your Job!

There’s not really an official or “formal” recognized difference between drug screen and drug test. However, there definitely is a big difference between the two, and knowing that difference could result in you whether or not you get hired for your new job – or fired from an existing one (if they enforce randomized drug testing).

Basically, a “drug screen” is a quick scan of bodily fluid or cellular tissue (urine, blood, hair, saliva, etc) that looks for the presence of known drug metabolites.

When thinking of a drug screen, think speedy: scans are speedy, but tests take time. Drug tests are much more involved than a simple speedy screen, and take a lot longer.

A lot of people don’t realize, however, that neither a drug screen or a drug test actually looks for the drug compound in question. Rather, they look for the presence of the compound’s known metabolites.

A metabolite is a chemical compound that’s a smaller, “broken down version” of the compound in question. In the case of marijuana (which tests for the use of THC), the metabolite that drug tests and drug scans look for is usually THC-COOH.

Almost immediately after you consume THC (whether it be via smoking, vaping, edibles, etc), the digestive system and various other metabolic pathways in the body will start breaking down the active compound into smaller metabolites. THC-COOH is the primary metabolite in question, and it can stay in human tissue for months on end, depending (among other things) on the frequency of use and the metabolic rate of the consumer.

Drug Scans vs. Drug Tests… What is a Drug Screen?

Like we said, a drug scan is a quick initial screening that tests your urine (or other bodily fluid/tissue) for the presence of THC metabolites.

By far the most common type of drug screen that employers use is EMIT screening, otherwise known as Enzyme Multiplied Immunoassay Technique.

This technique is quick, simple, cheap (generally costs employers about $0.95 per drug tested for), and is generally pretty accurate. However, it is prone to false positives.

In fact, some estimates believe that up to 10% of failed drug tests in the U.S. can be attributed to false positives; this may not seem like a lot, but if it were you that tested positive, wouldn’t you want to know 100% for sure that it was actually positive, and not just a mistake?

Fortunately, most employers realize this and as such, whenever a potential employee tests positive, the initial screening will be sent off for a further, more detailed analysis. This is the drug test.

How is a Drug Test Different From a Drug Screening?

Remember the following saying when trying to remember the difference between drug screen and drug test: Tests Take Time. Drug tests are typically much more involved than “speedy” drug screenings, and they incorporate much more sophisticated equipment to confirm the presence of THC metabolites.

The “gold standard” of the full-length drug test in the American market is generally the MS/GC test, also known as Mass Spectrometry/Gas Chromatography testing.

When a potential employee takes an initial UDT (urine drug test) screening and the screen comes up positive, the urine sample will be sent off to a third-party MS/GC testing facility for confirmation of the THC-COOH metabolites.

You might be wondering, “why don’t companies just do a drug test every single time, instead of doing a screening first?”

Well, what it comes down to is cost. While drug screens are relatively cheap, actual MS/GC tests are fairly involved – and thus pretty expensive – so employers generally don’t want to waste money on them unless they’re absolutely necessary.

In fact, MS/GC tests can be so accurate that they can determine whether or not the urine sample is even from a human. Back in 2011, Brazilian mixed martial artist Thiago Silva found this out the hard way as his mandatory urine sample was deemed “non-human” by the Nevada State Athletic Commission (NSAC).

In any regard, if you ever do fail an initial drug screening for a new job (or for any reason for that matter), make sure that you rule out a false positive by mandating the sample be tested with MS/GC techniques. At the end of the day, it could mean the difference of having a job or not.

What Could Cause a Marijuana Test to Show Up Positive?

Another thing you might be wondering is “how can you get a false positive on a marijuana drug test?”

Well, one of the most popular “urban myths” is that you can test positive through second-hand smoke inhalation (aka “passive inhalation”), but studies have shown that this is virtually impossible. Unless you’re locked in a smart car with Snoop Dogg for about 12 hours straight, you’re not going to fail a drug test from secondhand smoke inhalation.

Neither are you going to fail a drug test from eating hemp foods. Some people think that there is trace amounts of THC in hemp-based foods supplements such as hemp protein powder, hemp seed, and hemp hearts, but this is a complete myth as nutritional hemp seeds do not contain THC (or any other active cannabinoids for that matter).

Here are a few other (much more practical) reasons for what can cause a false positive on a marijuana drug test:

  • Taking over-the-counter NSAID’s. Studies have shown this to be incredibly improbable, but it is known that over-the-counter Non-Steoroidal Anti-Inflammatory Drugs (NSAID’s) such as Advil, Motrin, Aleve, etc can skew initial EMIT screenings to the point that they would show up positive. However, the subsequent MS/GC drug test would quickly correct the results and deem the EMIT as a “false positive,” in which case the potential employer would not be subject to any penalization.
  • Taking efavirenz. Efavirenz (Sustiva) is a relatively common prescription medication for HIV/AIDS patients, and it is known to be able to cause false positives on both EMIT screenings and MS/GC tests.
  • Consuming CBD oil. This is far and away the most “worrisome” thing for cannabis users, and it can end up causing both a failed drug screening and a failed drug test. Full-spectrum CBD oils (and other full-spectrum CBD products) do in fact contain trace amounts of THC, thus it is entirely possible that if consumed frequently enough, THC-COOH metabolites can build up to high enough levels that users would fail a test. This can – and has – happened in the past, and there is typically not much you can do about it other than plead with your MRO (medical review officer).

If you take CBD oil or other CBD-infused products on a daily basis and are concerned about failing an upcoming drug test, you may want to switch to CBD isolate oils instead, as these are 100% THC free.

Final Thoughts on the Difference Between a Drug Test and a Drug Screen

Well, hopefully you now know the difference between a drug screen and drug test. Simply put, drug screens are cheap options that provide employers with a quick and initial screening, while MS/GC drug tests are in-depth analysis that are used to verify and confirm the presence of THC and/or its metabolites.

Initial drug screenings are prone to false positives, so if you fail one, make sure that you verify with your employer that the screen has been confirmed with an MS/GC test. Otherwise, it could be the difference between having a job and not.