Comparing the Effects of the EU- Versus the US-JUUL Pod in a Sample of UK Smokers: Nicotine Absorption, Satisfaction, and Other Nicotine-Related Subjective Effects.

Introduction: Pod Vaping Devices (PVD) such as JUUL have become extremely popular in the United States although their uptake and use in the United Kingdom remain lower. A key difference between the United States and the United Kingdom is the nicotine strength legally permitted, typically 59 mg/mL in the United States but capped at 20 mg/mL in the United Kingdom and European Union. This may limit the ability of EU vaping devices to deliver satisfactory nicotine levels. The primary aim was to compare the EU- (18 mg/mL nicotine strength) with the U.S.-JUUL (59 mg/mL) on daily smokers' subjective experiences, craving relief, and blood nicotine levels.

Aims And Methods: Double-blind, counterbalanced within-participants design with two conditions: 18 mg/mL versus 59 mg/mL. On two separate occasions, UK smokers (N =19, 10 males, 9 females) vaped ad libitum for 60 mins and provided blood samples at baseline 5, 15, 30, and 60 min. Subjective effects (incl. satisfaction) were measured at 10 and 60 min and, craving and withdrawal symptoms (WS) at baseline, 10 and 60 min.

Results: Satisfaction did not differ between conditions. There was a significant interaction between Time and Nicotine concentration for Nicotine Hit (p = .045). Mean self-report of Nicotine Hit increased under the use of the 59 mg/mL from 10 to 60 min and decreased under the 18 mg/mL. Participants reported higher Throat Hits following use of the 59 mg/mL (p = .017). There were no differences in other subjective effects including craving, WS relief (ps > .05). Liquid consumption was doubled under the 18 versus the 59 mg/mL (p = .001) and nicotine boost was significantly higher in the 59 mg/mL at all time-points (p ≤ .001).

Conclusions: The results did not support our hypotheses that satisfaction, craving, and withdrawal reduction would be higher with the 59 mg/mL JUUL. This could be because of the doubling of liquid consumption in the 18 mg/mL. Whether satisfaction and craving relief persist over the longer-term outside of the lab remains to be determined.

Implications: In a 60-min ad-lib vaping session, the EU-JUUL was found to produce comparable satisfaction, craving- and withdrawal relief as the U.S.-JUUL in this sample of UK smokers. These findings could suggest that the higher nicotine concentrations available in PVDs in the United States are not necessary for providing satisfaction and improving craving and WS. However, this was at the expense of a considerable increase in liquid consumption indicative of compensatory puffing.