ALPHA-BENZYL-N-METHYLPHENETHYLAMINE (BNMPA), AN IMPURITY OF ILLICIT METHAMPHETAMINE SYNTHESIS - PHARMACOLOGICAL EVALUATION AND INTERACTION WITH METHAMPHETAMINE

Methamphetamine is a popular drug of abuse, readily synthesized in cla ndestine laboratories. Illicitly obtained methamphetamine is frequentl y impure, containing various purposefully added diluents and adulteran ts, as well as impurities of manufacture and origin. Few impurities ha ve been studied in vivo and limited information exists concerning thei r pharmacology/toxicology. One such impurity of manufacture is alpha-b enzyl-N-methylphenethylamine (BNMPA). Acute toxicity and spontaneous a ctivity (locomotor) studies were conducted with this compound alone an d in combination with S(+)-methamphetamine (METH) in male, ICR mice. I n the acute toxicity studies, BNMPA was evaluated for convulsant activ ity. While BNMPA also produced some behavioral disturbances similar to those seen with methamphetamine (e.g., stereotopy) at doses greater t han 30 mg/kg, no tonic-clonic convulsions were noted until pre-termina l convulsions at 50 mg/kg. METH alone produced tonic-clonic convulsion s at terminal doses of 70 mg/kg. When BNMPA was given in combination w ith METH, there was no readily apparent change in the convulsion profi le from that of METH given alone. In spontaneous activity studies, dos es of BNMPA ranging from 1 mg/kg to 50 mg/kg failed to alter locomotor activity significantly from controls though 5 mg/kg METH alone signif icantly increased spontaneous activity. In addition, increases in spon taneous activity elicited by 5 mg/kg METH were not affected when METH was given with 5 mg/kg BNMPA. White BNMPA appears to have toxic effect s in the central nervous system (CNS), the failure to affect locomotor activity or alter either METH-induced increases in spontaneous activi ty or METH-induced convulsions suggests that the two agents are produc ing their effects through distinct mechanisms.