Current Cutoff Levels for Toxicology
• Codeine
1. Codeine metabolizes mainly to morphine, but hydrocodone is a minor metabolite as well (up to 11% of the codeine concentration).
• Morphine
1. Hydromorphone is a minor metabolite of morphine (up to 2.5% of the morphine concentration).
2. Morphine is manufactured from codeine (demethylation). Codeine levels less than 1% of the morphine concentration are most likely an impurity present from the manufacturing process and should not be considered evidence of Codeine use.
3. Morphine is a metabolite of heroin and is found in the urine of heroin users. In the illicit manufacturing of heroin, small amounts of codeine is often present as an impurity. Presence of codeine does not rule out heroin use; however, the ratio of morphine to codeine can be helpful in discriminating between heroin and codeine use. See discussion on Poppy Seeds below.
• Hydrocodone
1. Hydrocodone metabolizes to Hydromorphone.
2. Hydrocodone is a pharmaceutical impurity of the Oxycodone production process. It may be present in very small amounts with high levels of Oxycodone (less than 4% of the oxycodone level).
3. Hydrocodone is a minor metabolite of codeine (see Codeine section above).
• Hydromorphone
1. Metabolite of hydrocodone.
2. Minor metabolite of morphine.
Opiates and Poppy Seeds Summary
• The pattern most consistent with poppy seed consumption is: morphine and codeine both present, morphine < 5000 ng/mL, codeine about one tenth the morphine concentration, and 6-MAM (heroin metabolite) not detected.
• If both morphine and codeine are present, but the codeine concentration is greater than half the morphine concentration, the positive result is probably due to codeine use, and is almost certainly not due to poppy seeds.
• If morphine is present at less than 5000 ng/mL but codeine is undetectable, the positive result is probably not caused by poppy seeds.
• If morphine is very high (> 5000 ng/mL), the positive result is probably not caused by poppy seeds.
• 6-MAM is a heroin metabolite that is found only in the urine of heroin users and is not found in urine of a person who has eaten poppy seeds. It can be ordered as a separate test if heroin use is suspected. A positive result for 6-MAM is firm evidence of heroin use. Failure to detect 6-MAM does not rule out heroin.