Why this exists

Toxicology is the component of this program with the weakest evidence behind it, and we would rather say that on its own page than let an agency discover it later.

The Agency for Healthcare Research and Quality’s 2020 comparative effectiveness review on opioid treatments for chronic pain asked directly about the effectiveness of risk mitigation strategies including urine drug screening. Its finding, verbatim: “No study evaluated the effectiveness of risk mitigation strategies, such as use of risk assessment instruments, opioid management plans, patient education, urine drug screening, prescription drug monitoring program data review, monitoring instruments, more frequent monitoring intervals, pill counts, abuse-deterrent formulations, or avoidance of co-prescribing of benzodiazepines on risk of overdose, addiction, abuse or misuse.” That is not a negative finding. It is an absence of evidence, and it covers most of the standard risk-mitigation toolkit, not only testing.

So why include it at all? Because clinicians order these tests, agencies fund them, and results are acted on today regardless of what the evidence base says. Given that, the question worth answering is not whether testing happens but whether it is done in a way that can be defended — and whether the result can be trusted to belong to the patient it is attached to. That is what “custodial” means here. The full evidence picture, including the interpretation problem, is on the urine drug testing page.

How it works

• Documented chain of custody from collection to result, anchored to the patient by DNALock rather than to a label.
• Salivary collection where appropriate, which is observed without being degrading — a consideration that gets left out of procurement documents and matters enormously to patients.
• Confirmatory testing before any result is acted on. Immunoassay results are presumptive. Treating a presumptive positive as a finding is the single most common way this goes wrong.
• Results returned with interpretation, including expected findings. A patient testing positive for the medication they were prescribed is the normal case and should never generate an alarm.
• A route to dispute a result, which a chain of custody is what makes possible.

Questions this raises

If the evidence for drug testing is weak, why offer it?

Because testing is already being done and acted on everywhere, and the realistic choice is not between testing and no testing but between testing that can be defended and testing that cannot. What we will not do is describe it as proven. The AHRQ review found no study evaluating whether it mitigates risk at all. See absence of evidence is not evidence of absence — and not evidence of effect either.

Can a drug test result get someone removed from treatment?

It should not, and CDC says so explicitly in its 2022 guideline. A program in which testing leads to dismissal has inverted the purpose of testing, because the patient most in need of continued care is the one whose result was unexpected. Our note on what a well-run taper looks like covers the alternative.