AIM To describe systemic nicotine exposure and subjective effects of electronic cigarettes (e-cigarettes) in people who use both e-cigarettes and cigarettes (dual users), including within-subject comparisons of e-cigarette and cigarette use. DESIGN Two-arm, counterbalanced crossover study. Participants used their usual brand of e-cigarette or cigarette during a standardized session in a 2-week study. SETTING Research ward, San Francisco, California, USA. PARTICIPANTS Thirty-six healthy (8 women, 28 men) participants. MEASUREMENTS Plasma nicotine was analyzed by gas chromatography-tandem mass spectrometry; nicotine withdrawal, urge to smoke and vape, affective states, craving, satisfaction, and psychological reward were measured by standardized questionnaires. FINDINGS Compared with cigarettes, average maximum plasma nicotine concentration (Cmax ) was lower with e-cigarettes [6.1±5.5 ng/ml (mean, SD) vs 20.2±11.1 ng/mL, p<0.001] and time of maximal concentration (Tmax ) was longer [6.5±5.4 min vs 2.7±2.4 min, (p<0.001)]. Use of both products resulted in a reduction in the severity of withdrawal symptoms, negative affect, and urge to use either product. E-cigarettes were less rewarding and satisfying and reduced craving to a lesser degree than cigarettes. We were not able to detect any differences in withdrawal symptoms, affective states, and urge to smoke cigarettes between e-cigarette and cigarette use. CONCLUSION Systemic nicotine exposure was on average lower with single use of e-cigarettes compared with cigarettes and e-cigarettes was judged to be less satisfying and rewarding and reduced craving less than cigarettes.

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双重使用者尼古丁摄入量的差异及其对电子烟和可燃卷烟的影响

目的 描述同时使用电子烟和香烟（双重使用者）的人群中电子烟（电子烟）的全身尼古丁暴露和主观影响，包括电子烟​​和香烟使用的受试者内比较。设计 双臂平衡交叉研究。在为期 2 周的研究中，参与者在标准化会议期间使用了他们常用品牌的电子烟或香烟。设置研究病房，旧金山，加利福尼亚，美国。参与者 三十六名健康（8 名女性，28 名男性）参与者。测量通过气相色谱-串联质谱法分析血浆尼古丁；尼古丁戒断、吸烟和电子烟的冲动、情感状态、渴望、满意度和心理奖励通过标准化问卷进行测量。发现 与香烟相比，电子烟的平均最大血浆尼古丁浓度 (Cmax) 较低 [6.1±5.5 ng/ml (mean, SD) vs 20.2±11.1 ng/mL, p<0.001]，最大浓度时间 (Tmax) 更长 [6.5 ±5.4 分钟 vs 2.7±2.4 分钟，(p<0.001)]。使用这两种产品导致戒断症状、负面影响和使用任何一种产品的冲动的严重程度降低。与香烟相比，电子烟的回报和满足感较低，并且减少的渴望程度也较低。我们无法检测到电子烟和香烟使用之间在戒断症状、情感状态和吸烟冲动方面的任何差异。结论 与香烟相比，单次使用电子烟的全身尼古丁暴露平均较低，并且电子烟的满意度和奖励性较差，并且对烟瘾的减少程度低于香烟。