Preliminary evidence from planarians that cotinine establishes a conditioned place preference.

While the psychoactive stimulant nicotine has been the subject of extensive research, considerably less attention has focused on other compounds found in either tobacco smoke or that are nicotine metabolites. Recent papers have suggested that some of the compounds in question may either alter nicotine's effects or have reinforcing properties themselves, although they would only be experienced after consumption of tobacco. The potential for these compounds to function as reinforcers or to potentiate the reinforcing properties of nicotine merits investigation.