Truck in the desert

What you need to know if you plan to begin trucking school, and you have consumed any cannabis recently.

THC & Truck Driving School Requirements

Many states now allow both recreational and medicinal consumption of cannabis for adults. This creates a lot of confusion for individuals that are, or will be subject to DOT drug testing. DOT cutoff levels for THC are 15ng (nanograms per milliliter). This is an exceptionally low level and there are not reliable over the counter drug tests that check THC at this level. Most over the counter drug tests have a 50ng cutoff level for THC which often gives individuals a false sense of security regarding their ability to pass a DOT test after consuming cannabis.  It is advised that if you expect to be doing a DOT drug test and you have used or been in contact with THC, getting a preliminary non-DOT drug test with a 15ng THC cutoff is highly advised. Your career in a safety sensitive field is at risk if you do not take the proper precaution to ensure you are ready to pass a DOT drug test. The presence of THC (tetrahydrocannabinol) in your system, and how long it will take to metabolize, depends on various factors, including your metabolism, frequency of use, dosage, and the type of drug test being conducted. While it’s not possible to guarantee the complete elimination of THC within a specific timeframe, there are some strategies you can follow to help expedite the process.

Ensure Passing a Drug Test

Abstain from cannabis

Cease any cannabis consumption, including smoking, vaping, or consuming edibles. This also includes all CBD products, or over the counter cannabis products claiming to have minimal THC. This is crucial as it allows your body time to metabolize and eliminate THC.


Drink plenty of water to stay hydrated. This may help dilute your urine and potentially reduce THC metabolite levels. However, excessive water intake immediately before the test might lead to a diluted sample, which could be flagged as suspicious.

Exercise regularly

Engaging in regular physical activity, such as cardio exercises, can help burn fat cells where THC metabolites tend to accumulate. However, avoid intense exercise close to the test, as this may temporarily release more THC metabolites into your bloodstream.

Eat a healthy diet

Focus on a balanced diet rich in fiber, fruits, and vegetables. These foods can support your body’s natural detoxification processes and promote overall health.

Consider detox products: Some detox products, such as detox drinks or kits, claim to aid in eliminating toxins from your system. However, their effectiveness and reliability are often debated, and they may not guarantee desired results. Any flushing or masking agents sold at smoke shops can actually produce an altered sample which may result in an automatic fail.

Give yourself ample time

THC metabolites can linger in your system for several days or even weeks, depending on usage patterns. The best way to ensure THC is out of your system is to abstain from cannabis for an extended period before the drug test.

Remember, these strategies may help accelerate the elimination of THC, but they don’t guarantee immediate results. It’s essential to consult with a healthcare professional or testing expert for personalized advice based on your specific situation.

Take a preliminary screening as indicated above. You have likely invested a lot of time and money to receive the training and experience to enter your career field. You would need to contact a DOT qualified SAP to help you become eligible to return to duty, before even beginning your career. Do not risk it if you can take precautions to ensure your ability to test negative. To find a testing site or clinic to help you with a preliminary screening we suggest that you do an internet search for “occupational drug testing near me.” If you guess wrong about whether you are ready to pass a DOT test, you can end up with clearinghouse violation and be subject to completing the return to duty process. This is a huge barrier for individuals starting out in the industry that have little experience.