What is a Urine Drug Test?
A urine drug screening detects drug metabolites in urine. These metabolites are not the original drugs themselves; rather, they are substances your body produces after it processes the drug. As a result, a urine drug test can identify the use of many commonly abused illegal and prescription drugs. For example, it can screen for cocaine, methamphetamines, amphetamines, barbiturates, benzodiazepines, marijuana, PCP, opiates, and methadone.
Why it’s done?
- Employers often use urine drug testing to determine if an individual can be a safe and productive employee.
- Additionally, the law requires some employees—especially those in transportation—to pass a urine drug test before they can perform safety-sensitive work, as outlined by U.S. Department of Transportation regulations.
Urine Drug Tests
Order Urine Drug TestScreening Test
The first test in a urine drug screening is the immunoassay, also known as the screening test. This screening test offers a cheap and fast way to check for drug use. In most cases, the lab reports these tests as negative and releases them without further testing. If the immunoassay detects something, the lab sends the sample for additional testing. We never refer to a non-negative screening test as “positive” because many substances can trigger a non-negative result. However, we consider a negative result conclusive. This method doesn’t measure the drug levels in the urine but simply determines whether the amount is above or below the cutoff.
Confirmation Test
If the immunoassay, or screening test, shows a non-negative result, the lab conducts a more specific test to confirm the presence of the drug. This confirmation test, called gas chromatography/mass spectrometry (GC/MS), analyzes the sample only for the specific drug or drugs flagged during the screening. This process eliminates any chance of a false positive.
What is a False Positive Result?
A false positive occurs only when no confirmation test is performed and a medical review is skipped. In contrast, GC/MS testing provides definitive and defensible results. Unfortunately, some irresponsible employers and drug testing providers skip confirmation of non-negative screening tests, which exposes them to serious legal risks.
At InOut Labs, we ensure that every non-negative screening test goes through both confirmation testing and medical review—without exception.
How a Urine Drug Test is Conducted ?
The Department of Health and Human Services outlines urine drug test collection procedures in 49 CFR Part 40. Generally, these procedures remain consistent across both regulated and non-regulated testing. In most cases, regulated testing applies to employees under the US Department of Transportation, commonly known as DOT drug testing.
During the step-by-step urine specimen collection process, the collector verifies the donor’s identity, secures the collection area to prevent cheating, and completes the necessary paperwork to establish a clear chain of custody. As a result, there is no chance for someone’s specimen to be confused with another’s.
What About Prescriptions?
Some prescribed medications will be detected in a urine drug test. For this reason it’s important the a Medical Review Officer (MRO) be involved. An MRO reviews all positive drug test results and will verify all prescriptions. If a positive result is due to a valid prescription, the result is reported as a negative. This protects both the employer and the donor. For more on the MRO, see here.