Opioids on a Drug Test: Which Ones, and at What Cutoffs

Four lines, not one drug

On an older panel, “opiates” meant codeine, morphine, and heroin. The current federal panel is wider and more specific, and each pair carries its own numbers Source 1eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026:

• Codeine and morphine - 2,000 ng/mL to screen, 2,000 ng/mL to confirm
• Hydrocodone and hydromorphone - 300 to screen, 100 to confirm
• Oxycodone and oxymorphone - 100 to screen, 100 to confirm
• 6-acetylmorphine - 10 to screen, 10 to confirm

The spread is the point. Codeine and morphine are twenty times higher than oxycodone, so a reading that clears one pair tells you nothing at all about another.

Why 6-acetylmorphine is the specific one

6-acetylmorphine is a heroin metabolite. Morphine in a specimen can have come from more than one place; 6-AM is the marker that points to heroin in particular, and it carries the lowest cutoff on the panel at 10 ng/mL in both stages Source 1eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026.

Fentanyl is not on the DOT panel

Federal (DOT): fentanyl and norfentanyl are absent from the cutoff table in the current regulation Source 1eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026. DOT has proposed adding fentanyl to the panel, and that proposal has not taken effect Source 2Federal RegisterNPRM — Addition of Fentanyl to the DOT Testing Panel — checked 17 Aug 2026. We re-checked the regulation on 18 August 2026, and it remains as amended in May 2023.

If someone tells you a DOT test covers fentanyl today, they are describing a proposal rather than the rule.

Prescriptions are the common case

Most opioid positives have a prescription behind them. As with any analyte, the medical review officer considers whether there is a legitimate medical explanation before a laboratory positive is verified Source 3eCFR49 CFR Part 40 — Procedures for Transportation Workplace Drug and Alcohol Testing Programs — checked 17 Aug 2026. And that is where the prescription and its documentation belong.

The EEOC has published guidance for employees on codeine, oxycodone, and other opioids Source 4EEOCUse of Codeine, Oxycodone, and Other Opioids: Information for Employees — checked 17 Aug 2026. Two limits on it are worth knowing before you rely on it: it is technical assistance and does not carry the force of law, and it does not address DOT or safety-sensitive roles. If you are in a regulated job, it is not your document.

What a number above a cutoff does not establish

A concentration above a cutoff is not a measure of impairment, of dose, or of when a substance was taken. The cutoffs exist to separate a reportable result from an unreportable one, and that is all they do Source 1eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026Source 5HHSMandatory Guidelines for Federal Workplace Drug Testing Programs — Authorized Testing Panels — checked 17 Aug 2026.