10 - Controlled Laboratory Studies on the Effects of Cocaine in Combination with Other Commonly Abused Drugs in Humans

Abstract

Multiple drug use and abuse is well documented among drug abusers in general and cocaine abusers in particular. Multiple drug use among cocaine abusers is a significant public health concern because it is associated with increased morbidity. Data from clinical samples also document high levels of multiple drug use and abuse among cocaine abusers. The study by Higgins and colleagues illustrates the performance effects of cocaine and alcohol, alone and in combination. Controlled laboratory studies that examined the cardio-vascular effects of cocaine alcohol combinations in humans generally support the position that the effects of the drug combination are of larger magnitude than those observed with cocaine alone. This chapter highlights the fact that regular cigarette smoking is more common among cocaine abusers than the general population. Studies suggest that cocaine may increase the reinforcing effects of nicotine, although this effect could be the result of a nonspecific increase in overall activity levels. Experimental results of cocaine-nicotine interactions in humans are sparse, but this chapter elucidates three tentative conclusions. The prevalence of multiple drug abuse among cocaine abusers is striking.