However, this conversion also occurs under normal conditions. Note that little is known about the impact the ingestion of the THC precursors has on the urinalysis test for THC metabolites. THC metabolites can be found in the urine following passive inhalation episodes but these are well below most cut-off levels. Drugs metabolized to methamphetamine include benzphetamine, deprenyl, dimethylamphetamine, famprofazone, fencamine, and furfenorex. Drugs metabolized directly to amphetamine include amphetaminil, clobenzorex, ethylamphetamine, fenethylline, fenproporex, mefenorex, mesocarb, and prenylamine.
Poppy seeds contain morphine.
Treatment with codeine and lidocaine will cause a positive urine test for cocaine.