Substance guides

How long does morphine stay in your system?

Published June 8, 2025 · 7 min read · Updated April 2026

Reviewed for accuracy by licensed clinical professionals.

Morphine has a half-life of 2-4 hours but its metabolites remain detectable longer. Morphine is also the metabolite of heroin and codeine, creating testing complexities.

Detection by test type

Urine: 2-3 days. Morphine is the primary analyte on standard opioid panels. Blood: 12-24 hours. Saliva: 1-2 days. Hair: up to 90 days.

Testing complexities

Morphine appears on drug tests from morphine use, heroin use (heroin metabolizes to morphine), and codeine use (codeine metabolizes to morphine). Confirmatory testing including 6-MAM and codeine ratios helps determine the source.

Poppy seed warning

Consuming large amounts of poppy seeds can produce a positive morphine test at standard cutoffs. The federal workplace cutoff was raised to 2000 ng/mL specifically to reduce poppy seed false positives.

Authoritative sources

This article references guidelines from: SAMHSA · NIDA · ASAM

Frequently asked questions

How long does morphine stay in urine?

2-3 days for standard dosing.

Can poppy seeds cause a positive morphine test?

Yes. Large amounts of poppy seeds can produce a positive result, though raised cutoff levels have reduced this issue.

Does heroin show as morphine on a drug test?

Yes. Heroin metabolizes to morphine. Specialized 6-MAM testing confirms heroin specifically.

Disclaimer: Informational only. Not medical advice. SAMHSA: 1-800-662-4357.