A comparative study of the behavioural responses induced by chronic administration of methamphetamine and amphetamine in mice.

The behavioural effects induced in mice by the chronic administration of (+)-methamphetamine (MA) and (+)-amphetamine (A) at three dosages were studied under identical research conditions. The results indicated that MA exerted greater central excitation than A. At the dosage 0.64 mg/kg quiescence was decreased and activity increased more by MA than A. Hyperactivity induced at the 2.5 mg/kg dosage was sustained over a longer time period with MA. Frenzied self-tearing emerged with repeated drug administration at the 10 mg/kg dose in more MA-treated than A-treated animals.