Urine thebaine determination by liquid chromatography tandem mass spectrometry after poppy seed consumption.

Laboratories are challenged to distinguish whether a positive urine morphine result is due to heroin use or possible poppy seed consumption. Thebaine is an opium alkaloid that has been shown to be present in the urine of individuals who have consumed poppy seeds, as well as those who have used opium. It is not present in heroin. We present a sensitive, specific liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for thebaine. We show that thebaine is detectable after consumption of two different poppy seed-containing products for up to 72 h in urine. We discuss limitations of the assay and suggest how the test might best be used.