How to Read a Drug Test and Understand Your Results Clearly

What Is a Drug Test and How Are Results Reported?

A drug test is a laboratory analysis of a biological specimen such as urine, hair, saliva, or blood to detect the presence of drugs or their metabolites. Results are reported as either negative (no drugs detected above cutoff) or non-negative (drugs detected above cutoff).

AMH Nationwide routes collections through five national lab networks: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, and ExperTox. All non-negative screens are reviewed by a certified Medical Review Officer (MRO) to confirm results and rule out legitimate medical explanations.

How Can You Tell If You Passed a Drug Test?

You pass a drug test when the specimen shows no drugs or metabolites above the laboratory’s cutoff levels. A negative result means the test did not detect drug use within the detection window of the specimen type.

Passing does not mean zero traces of drugs, as low levels below cutoff thresholds are considered negative. Each drug has specific cutoff levels based on SAMHSA guidelines or other regulatory standards.

What Does a Positive Drug Test Look Like?

A positive drug test means the specimen contained drug levels above the established cutoff. The initial immunoassay screen flags the sample as presumptive positive, and a confirmatory test using GC-MS or LC-MS/MS verifies the specific drug and concentration.

The lab report will show the drug name, concentration level, and whether it exceeds the cutoff. The Medical Review Officer reviews medical history and prescriptions before finalizing the positive result.

Can You See an Example of Drug Test Results?

Drug test results typically include the drug name, test method, cutoff level, and measured concentration. For example, a urine test report may show THC with a cutoff of 50 ng/mL and a measured level of 120 ng/mL indicating a positive result.

Hair test results will list detected substances with detection windows covering weeks to months depending on hair length. Each lab network formats reports slightly differently but all contain key data for interpretation.

What Are Drug Test Levels and Cutoffs?

Drug test levels refer to the measured concentration of a drug or metabolite in the specimen, usually in nanograms per milliliter (ng/mL). Cutoff levels are minimum thresholds established to distinguish between negative and positive results and avoid false positives.

Cutoffs vary by drug and specimen type. For example, the SAMHSA cutoff for THC in urine is 50 ng/mL. Levels below cutoff are reported negative even if trace amounts are present.

How Does Reading a Hair Drug Test Differ from Urine?

Reading a hair drug test involves interpreting results from a longer detection window, usually up to 90 days, compared with urine which detects recent use typically within 1-3 days. Hair tests report presence or absence of drugs in hair segments rather than concentration levels.

Hair tests are used mainly for non-DOT safety sensitive roles while urine is standard for DOT-regulated testing under 49 CFR Part 40. Hair test results also undergo MRO review to confirm findings.

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