An enduring fixture of prohibitionist literature is the claim that, given the option, animals will self-administer cocaine until they overdose or starve to death by selecting it in preference to food. Research supporting this contention frequently involves animals placed in unnatural conditions (isolated, immobilized, starved, etc.), and removing these stresses generally reduces cocaine self-administration.1,2

Researchers have previously found that providing rats with sweetened water significantly reduced their voluntary cocaine intake,3 and a recent study has reported that rats overwhelmingly prefer water sweetened with saccharin or sucrose over cocaine.4 When presented with an either/or choice eight times a day, 94% of test rats selected the non-caloric sweetener saccharin over a "behaviorally effective" dose of cocaine (0.25 mg, i.v.). While it took the rats eleven days to develop a statistically reliable preference for selecting cocaine over nothing, it took only two days to develop a statistically reliable preference for saccharin over cocaine.4

According to the researchers, "the preference for saccharin sweet taste was not surmountable by increasing doses of cocaine and was observed despite either cocaine intoxication, sensitization or intake escalation--the latter being a hallmark of drug addiction". Pointing out apparently contradictory findings from previous primate studies that offered solid pellets instead of sweetened liquids, the researchers speculate that important differences may exist between the research methods or could be a result of inter-species differences between rodents and primates.