R Meatherall
Journal of analytical toxicology, 23(3), 177-186 (1999-06-16)
A procedure for the simultaneous confirmation of codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone in urine specimens by gas chromatography-mass spectrometry (GC-MS) is described. After the addition of nalorphine and naltrexone as the two internal standards, the urine is