Abstract Purpose The interaction between obesity and smoking is complex. Aim of this study is to compare the abstinence rates of smoking cessation pharmacotherapies vs electronic cigarettes in obese smokers. Methods 57 obese smokers (aged 41±8 years, BMI: 33.8 ±2.4 Kg/m2) visiting our unit from January 2016 to November 2022 were randomized into three smoking cessation therapy groups: 1. NRT (nicotine patch), 2. NRT + bupropion (NRT+bupr) and 3. Electronic cigarette (EC). Results There were not significant differences in severity of nicotine dependence and cigarette consumption (pack-years) between the three treatment groups. Furthermore, the three groups had similar age and prevalence of traditional risk factors. At the end of treatment period (3 months), 5/19 (26 %) and 9/19 (47%) of subjects under therapy with NRT alone and NRT + bupropion combination respectively, were abstinent from smoking while 10/19 (53%) of individuals using EC did not smoke combustible cigarettes. Left plot shows the continuous abstinence rates at 6 months. Continuous abstinence rates were similar in the NRT and NRT+bupropion group at 6 months compared to 3 months (end of treatment), while 8/19 (42%) of individuals using EC did not smoke. Interestingly , at 6 months among users of EC 6 continued vaping nicotine alone, 7 continued to smoke tobacco cigarettes while vaping and 4 continued smoking cigarettes alone. Nevertheless only 2 out of 19 participants in that group stayed abstinent from both combustible cigarette smoking and vaping. Blood pressure remained unchanged in all groups while weight decreased in the group treated with the combination of bupropion and NRT compared to NRT alone and EC groups (right plot, P<0.01). Conclusions Our preliminary data indicate that continuous abstinence rates at 6 months were higher in obese smokers receiving NRT+bupropion combination therapy compared to those of individuals who used NRT alone. There is also a low abstinence rate of both cigarette smoking and vaping among individuals using EC as an aid for smoking cessation. The NRT+bupropion combination therapy was associated with a favorable effect on weight change in obese smokers.EC vs pharmacotherapy in obese smokers