Similar discriminative-stimulus effects of d-amphetamine in women and men

The results of controlled non-human animal and human laboratory studies are mixed regarding whether women and men respond differently to stimulant drugs. In order to assess potential gender differences in the effects of d-amphetamine, we conducted a retrospective analysis of six studies conducted in our laboratory that used identical procedures and measures. Thirteen women and fourteen men learned to discriminate 15 mg oral d-amphetamine. After acquiring the discrimination (i.e., ≥ 80% correct responding on 4 consecutive sessions), the effects of a range of doses of d-amphetamine (0, 2.5, 5, 10, and 15 mg) alone and in combination with other drugs, were assessed. Only data from sessions in which d-amphetamine was administered alone were included in this analysis. d-Amphetamine functioned as a discriminative stimulus and dose-dependently increased drug-appropriate responding. Women and men did not differ in their ability to discriminate d-amphetamine. Women and men differed on participant-ratings of high (women < men), nausea (women > men) and sluggish (women < men), women also experienced greater increases in diastolic pressure than men. Because the results of this study may have been confounded by the training procedures, future research should use other behavioral arrangements (e.g. drug self-administration) to determine if women and men respond differently to the effects of d-amphetamine.