Abuse of smoking methamphetamine mixed with tobacco. III. Urinary metabolites of N-cyanomethylmethamphetamine, a pyrolysis product formed by smoking methamphetamine in tobacco, and species difference in its metabolism between rat and mouse.

1. N-cyanomethylmethamphetamine (CMMA) or methamphetamine (MA) was given intraperitoneally to rat and mouse (1, 3, 10 mg/kg). The basic urinary metabolites of CMMA were determined by mass spectrometry (MS) and compared with those of MA. 2. N-formylmethamphetamine (FMA), a specific metabolite of CMMA, was found in both rat and mouse urine. However, the dose percentage of FMA excreted in mouse urine was less than one-quarter of that in rat urine. 3. No CMMA was detected in rat or mouse urine collected within 72 h after dosing. All other basic metabolites of CMMA except FMA, i.e. MA, amphetamine (AP), p-hydroxymethamphetamine (OHMA) and p-hydroxyamphetamine (OHAP), were the same as those of MA in both species. 4. The excretion pattern of the urinary metabolites of CMMA was similar to that of MA except FMA in both species, though the amount of each metabolite of MA administration was larger than that of CMMA administration. However, in urinary excretion of FMA and hydroxylated metabolites, definite species differences were observed between rat and mouse. 5. A trace amount of FMA was identified in the urine of an abuser who had smoked MA with tobacco.