Many employees and commercial drivers want to know which medications can cause a failed drug test. The answer depends on the type of drug test being used, but in general, only specific categories of drugs are targeted.
Understanding which medications are tested, and which can cause complications, helps avoid confusion and potential compliance issues.
What Standard Drug Tests Screen For
Most workplace drug tests, including those regulated by the DOT, screen for five drug categories:
- Marijuana (THC)
- Cocaine
- Amphetamines
- Opiates
- Phencyclidine (PCP)
These substances are chosen because they are commonly abused and can impair safety.
Prescription Medications That Can Cause Positive Results
Certain prescription drugs will appear on drug tests because they fall into these categories.
Amphetamines
- Adderall
- Vyvanse
Opioids
- Oxycodone
- Hydrocodone
- Morphine
- Codeine
Benzodiazepines (Non-DOT Panels)
- Xanax
- Valium
- Ativan
While benzodiazepines are not part of DOT testing, they may appear in expanded panels.
What Happens If You Have a Prescription?
A positive drug test does not automatically mean failure.
When a result is detected:
- A Medical Review Officer (MRO) reviews the result
- The employee is contacted
- A prescription can be verified
If the medication is legally prescribed, the result is typically reported as negative.
Medications That Cause False Positives
Some medications may trigger false positives during initial screening:
- Cold medications (pseudoephedrine)
- Antidepressants
- Antihistamines
- Anti-inflammatory drugs
However, confirmation testing eliminates these errors.
DOT vs. Non-DOT Testing
DOT drug testing is strict and limited to five drug categories.
Non-DOT testing may include:
- Benzodiazepines
- Barbiturates
- Synthetic drugs
This means the risk of detection varies depending on the testing program.
Key Takeaways
- Only certain drug categories are tested
- Prescription medications may appear but are verified
- False positives are corrected through confirmation testing
- DOT testing is more limited than non-DOT testing
Understanding how drug testing works helps employees remain compliant and avoid unnecessary concern.