Effects of labetalol treatment on the physiological and subjective response to smoked cocaine.
Adrenergic receptors mediate some of the physiological and possibly behavioral effects of cocaine. The purpose of this study was to investigate the effect of treatment with a peripherally acting adrenergic blocking drug labetalol on the cardiovascular and subjective response to repeated deliveries of smoked cocaine. In this double-blind, placebo-controlled, crossover study, 12 cocaine users were treated with a single 100 or 200 mg dose of labetalol, or placebo in each of three experimental sessions. Starting 2 h after the medication treatment, subjects received three doses of 0.4 mg/kg smoked cocaine, 30 min apart. Labetalol treatment significantly attenuated the cocaine-induced increases in heart rate and systolic blood pressure. This effect of labetalol on the cardiovascular response did not decrease with repeated cocaine deliveries. The subjective response to smoked cocaine deliveries was not affected by labetalol treatment. These results suggest that labetalol effectively attenuates the systolic blood pressure and heart rate increases induced by repeated doses of smoked cocaine, but does not alter subjective effects.
Sofuoglu
M
M
Department of Psychiatry, University of Minnesota, Minneapolis 55455, USA.
Brown
S
S
Babb
D A
DA
Pentel
P R
PR
Hatsukami
D K
DK
D018674:Adrenergic Antagonists / Q000494:pharmacology*; D016739:Behavior, Addictive / Q000523:psychology; D001794:Blood Pressure / Q000187:drug effects*; D003042:Cocaine / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D019970:Cocaine-Related Disorders / Q000523:psychology; D016578:Crack Cocaine; D018592:Cross-Over Studies; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007741:Labetalol / Q000494:pharmacology*; D008297:Male
D018674:Adrenergic Antagonists; D016578:Crack Cocaine; D018765:Dopamine Uptake Inhibitors; D003042:Cocaine; D007741:Labetalol