additional experiments tested the effects of chronic administration of drugs that were substituted ( d-amphetamine ) or were not substituted ( morphine ) for the training stimulus . d-amphetamine ( 2.5 mg/kg/8 hr for 7 days ) produced a 4-fold shift to the right of the dose-effect curve for the detection of both d-amphetamine and cocaine ;
C0011812
d-amphetamine
C0002658
amphetamine