Poppy Seed Consumption May Be Associated with Codeine-Only Urine Drug Test Results.

Area of Science:

• Forensic Toxicology
• Pharmacology
• Analytical Chemistry

Background:

• Poppy seed consumption can cause positive opiate urine drug tests, complicating interpretation.
• Existing guidelines use codeine concentrations and morphine-to-codeine ratios to differentiate poppy seed intake from codeine administration.

Purpose of the Study:

• To investigate the reliability of current guidelines in distinguishing poppy seed consumption from codeine administration.
• To assess urinary opiate levels after consumption of various poppy seed-containing food products.

Main Methods:

• Eleven participants consumed 10 different poppy seed food products.
• Urine samples were analyzed for codeine and morphine concentrations.
• Morphine-to-codeine ratios were calculated and compared to established cut-offs.

Main Results:

• Six of 33 urine samples (18%) from three food products tested positive for codeine and negative for morphine.
• These positive results had morphine-to-codeine ratios below 2, meeting criteria for codeine administration.
• Maximum urinary codeine concentrations did not exceed 1,300 µg/g creatinine in any case.

Conclusions:

• Consumption of poppy seed foods can produce results indistinguishable from codeine administration based on current urinary opiate concentration and ratio thresholds.
• Reliance on these thresholds alone may lead to misinterpretation of drug test results in cases of poppy seed ingestion.