Disputed Results Guide
Can a Drug Test Produce a False Positive?
Yes. No testing method is completely free of error. An initial screening result and a confirmed lab result are not the same thing. Questions can involve the method, specimen identity, cross-reactivity, medications, chain of custody, lab procedure and confirmation.
Quick answer
Can a Drug Test Be a False Positive?
- Yes. No testing method is completely free of error.
- A screening result is not the same as a confirmed result.
- Questions can involve method, specimen identity, cross-reactivity, medications, chain of custody and lab procedure.
- Discuss disputed results with defense counsel and the qualified lab or clinical professional involved.
Screen vs confirmation
A Screening Result Is Not the Same as a Confirmed Result
Flow from initial screen to confirmatory method and final reported result.
Initial screen
Non-negative / positive screen
Where applicable
Confirmatory method
Lab review
Final reported result
First step
What a Screening Test Does
Screens sort specimens quickly. They can react to substances with similar structures. A non-negative screen is not a final result.
Second step
What Confirmation Does
In laboratory and toxicology practice, a presumptive screen is often confirmed with an orthogonal method such as GC-MS or LC-MS/MS. Whether a given program requires confirmation depends on its rules. It reduces, but does not remove, every possible error.
Cross-reactivity
Medications and Cross-Reactivity
Some medications may cross-react with certain screens. This is a potential effect, not a guaranteed outcome. Tell the collector or lab about prescriptions as the program allows, and discuss with a qualified clinician.
Review points
Other Factors That Can Matter
Specimen identity, chain of custody, cutoff levels and lab procedures can all matter.
Next steps
If You Dispute a Result
Discuss disputed results with defense counsel and the qualified laboratory or clinical professional involved. Do not try to defeat or alter a test.
Legal note
Whether a result is used or disputed in court is a legal question. Defense counsel handles it; the court decides.
What ETS can and cannot do
Where Executive Treatment Solutions Fits
ETS is not a laboratory. ETS coordinates testing and keeps authorized records organized for counsel.
Responsibilities
Who Does What?
Laboratory
Screens, confirms and reports.
Qualified clinician
Reviews medications and medical factors.
Defense counsel
Handles disputed results.
Court
Decides legal consequences.
ETS
Coordinates testing and records.
Questions
False Positive Drug Tests: Frequently Asked Questions
Sources & Legal References
Federal workplace testing standard (reference only — not court rules)
Clinical / toxicology research
Confidential consultation
Organized Testing Support
ETS can coordinate testing and authorized records for counsel.
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