A qualitative and quantitative review of cocaine-induced craving: The phenomenon of priming

Drug-induced craving is thought to play an important role in relapse occasioned by a "slip", or an isolated use of a previously abused drug after a period of abstinence. Clinical experience suggests that acute exposure to cocaine elicits craving (hereafter referred to as "priming"); however, this has received surprisingly little attention in the clinical literature. Aims: The intentions of this review are to provide a qualitative review of the literature as well as a more stringent quantitative review of the existence and presence of cocaine-induced priming effects. Methods: In order to determine whether priming effects occur following cocaine administration, we conducted qualitative and quantitative reviews of studies in which participants received cocaine under experimentally controlled conditions in the laboratory. Results: The results of the qualitative review were equivocal, while the quantitative review revealed that cocaine administration was associated with a significant increase in craving for cocaine, and the effect size of this relationship was large. Conclusion: A review of the individual studies revealed marked variability, suggesting that priming effects did not occur consistently and that there may be factors that mediate or moderate the intensity of the priming effects induced by cocaine. The implications of these findings are discussed.