Evaluating the human abuse potential of concurrent use of electronic cigarettes and low nicotine cigarettes among adults who smoke.

The U.S. Food and Drug Administration has stated its intention to reduce the nicotine content of combustible cigarettes to render them less addictive. This study evaluated the impact of providing adults who smoke with both very low nicotine content cigarettes (VLNCCs) and electronic cigarettes (ECs) of varying nicotine content on measures of human abuse potential. Participants ( = 213) were adult combustible cigarette users. They smoked their usual brand cigarettes (UBCs) during Phase 1 (baseline; week 1) and were provided with and encouraged to exclusively use VLNCCs during Phase 2 (weeks 2-4). During dual-product Phases 3 (weeks 5-7) and 4 (weeks 8-10), participants received both VLNCCs and ECs (assigned to one of two EC devices in higher or lower nicotine concentrations and choice of flavor), with instructions to use them freely in Phases 3 and 4. Assessments included product use, exposure, acceptability, risk perception, and withdrawal-related measures. Results indicated that participants used significantly fewer UBCs during the VLNCC and dual-product phases and smoked fewer VLNCCs during the dual-product phases than the VLNCC-only phase. Neither EC liquid nicotine concentration nor flavor influenced product use. The three study product phases resulted in less product liking and more withdrawal symptoms than the UBC phase. These results suggest that adults who smoke are able to switch much of their tobacco product use from UBCs to VLNCCs and will substitute combustible UBCs and VLNCCs with noncombustible nicotine-containing ECs, but most remain dual users, at least in the short term. (PsycInfo Database Record (c) 2025 APA, all rights reserved).