Professor Jonathan Foulds Professor of Public Health Sciences and Psychiatry, Penn State University, College of Medicine, Pennsylvania, USA
Abstract
Introduction:
This study measured acute nicotine absorption in current e-cig users using their own device and compared it with absorption in a prior laboratory study using similar methods in traditional cigarette smokers.
Methods:
14 current e-cig users (10 using advanced e-cigs, 4 using cigalikes) completed the acute pharmacokinetic study and are compared with 9 traditional cigarette smokers. E-cig users were required to abstain from smoked tobacco for 4 days and from all sources of nicotine for 14 hours prior to the laboratory visit and required to have an exhaled baseline CO below 8 ppm. They were instructed to take a puff on their e-cig once every 20 seconds for 10 minutes (i.e. 30 puffs). Blood samples were taken at baseline and then 1,2,4,6,8,10,12 and 15 minutes after initiation of puffing. Procedures were similar for smokers.
Results:
E-cig users had used for an average of 9 months and their mean nicotine concentration in the liquid was 15.9 mg/ml. E-cig use resulted in a significant reduction in craving and total withdrawal score (both p<0.04). Overall, cigarette smokers obtained a significantly larger boost in blood nicotine (16.7 ng/ml) than e-cig users (8.2 ng/ml), and a significantly shorter time to peak (6.4 minutes versus 11.5). Cigalike users obtained a significantly lower mean boost in blood nicotine concentration than users of advanced e-cigs (1.8 v 10.8 ng/ml).
Conclusion:
While experienced users of advanced e-cigs can obtain a rate of nicotine absorption similar to that of traditional cigarettes, most obtain lower absorption, and users of cigalike models appear to absorb very little nicotine, even when using a relatively aggressive puffing schedule.
Source of funding: This work was supported by an internal grant from Penn State Clinical Translational Science Institute (supported by the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant UL1 TR000127), Social Science Research Institute, & Cancer Institute.
Declaration of interest: Jonathan Foulds does consulting for pharma companies involved in developing and marketing smoking cessation medicines (e.g Pfizer).
