Using smoking cessation medications for several weeks prior to quitting smoking facilitates quitting success, but how it does so is not clear. Candidate theories are that pre‐cessation medication enhances self‐efficacy, facilitates medication adherence post‐quit, induces aversion to smoking, reduces reward from smoking, or reduces the drive to smoke. We investigated these pathways using data from a large trial of nicotine preloading, using mediation analysis.. Please contact the library to request a copy of this article - http://bit.ly/1Xyazai