Discriminative-stimulus effects of modafinil in cocaine-trained humans.
Modafinil is a novel stimulant that is effective in the treatment of narcolepsy and excessive daytime sleepiness. In vitro and in vivo neuropharmacological data suggest that the mechanism of action of modafinil is distinct from that of prototypical abused stimulants like cocaine and d-amphetamine. In the present experiment, six human volunteers with recent histories of cocaine use learned to discriminate 150 mg oral cocaine HCL. After acquiring the discrimination (i.e. > or = 80% correct responding on 4 consecutive days), a range of doses of oral cocaine (50, 100, and 150 mg), modafinil (200, 400, and 600 mg), and placebo were tested to determine if they shared discriminative-stimulus and self-reported effects with 150 mg cocaine. Methylphenidate (60 mg) and triazolam (0.5 mg) were included as positive and negative controls, respectively. Cocaine and methylphenidate, but neither modafinil nor triazolam, produced cocaine-like discriminative-stimulus, subject-rated, and cardiovascular effects. The results of the present experiment suggest that cocaine discrimination in humans is pharmacologically specific within and across drug classes.
Department of Behavioral Science, University of Kentucky, Lexington, KY 40536-0086, USA. crush2@uky.edu
Craig R
CR
Rush
Thomas H
TH
Kelly
Lon R
LR
Hays
Adam F
AF
Wooten
D000328:Adult; D000704:Analysis of Variance; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology; D003042:Cocaine / Q000494:pharmacology*; D019970:Cocaine-Related Disorders / Q000523:psychology; D004193:Discrimination Learning / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077408:Modafinil; D011795:Surveys and Questionnaires
D001559:Benzhydryl Compounds; D000697:Central Nervous System Stimulants; D003042:Cocaine; D000077408:Modafinil