Behavioral pharmacological similarities between methylphenidate and cocaine in cocaine abusers.
Six human participants with recent histories of cocaine use were trained to discriminate 200 mg oral cocaine hydrochloride. A range of doses of oral cocaine (50-300 mg), methylphenidate (15-90 mg), triazolam (0.125-0.75 mg), and placebo were then tested to determine whether they shared discriminative-stimulus and participant-rated effects with 200 mg cocaine. Cocaine and methylphenidate dose-dependently increased cocaine-appropriate responding, produced prototypical stimulant-like participant-rated drug effects (e.g., increased participant ratings of Drug Liking), and increased heart rate and blood pressure. Triazolam produced low levels of cocaine-appropriate responding and impaired performance. Thus, consistent with previous studies, humans can reliably discriminate oral cocaine. Consistent with in vivo behavioral neuropharmacological data, the discriminative-stimulus, participant-rated, and physiological effects of oral cocaine and methylphenidate were similar.
Rush
C R
CR
Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, USA. crush2@uky.edu
Baker
R W
RW
D000328:Adult; D001519:Behavior / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003042:Cocaine / Q000494:pharmacology*; D019970:Cocaine-Related Disorders / Q000523:psychology*; D004192:Discrimination, Psychological / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D008297:Male; D008774:Methylphenidate / Q000494:pharmacology*; D008875:Middle Aged; D011597:Psychomotor Performance / Q000187:drug effects; D011795:Surveys and Questionnaires; D014229:Triazolam / Q000494:pharmacology
D000697:Central Nervous System Stimulants; D006993:Hypnotics and Sedatives; D014229:Triazolam; D008774:Methylphenidate; D003042:Cocaine