, 2008), 10 VAS items that assessed the direct effects of nicotine (Blank, Sams, Weaver, & Eissenberg, 2008), 14 VAS items that assessed the direct effects of the EC (Vansickel selleck chem inhibitor et al., 2010) as well as the total number of puffs taken during the ad lib period. Results Participants were former smokers who had tried to quit smoking an average (SD) of 3.9 (1.8) times in their lifetime, had quit smoking for 11.4 (5.4) months, and had been using ECs for 11.5 (5.4) months. Their average age was 33.4 (8.6) years, and they had completed 15.3 (2) years of education. Seven participants used devices that did not resemble tobacco cigarettes and housed higher voltage and/or longer lasting batteries than in previous work (e.g., Vansickel et al., 2010). Six participants used 18 mg/ml nicotine solution, one used 9, and the other used 24 mg/ml solution.

Plasma nicotine increased significantly from a baseline mean of 2 ng/ml (SEM = 0) to a mean of 10.3 ng/ml (SEM = 2) within 5 min of the first puff. Plasma nicotine reached a maximum mean concentration (M = 16.3 ng/ml, SEM = 4.5) by the end of the ad lib period (see Figure 1; relative to baseline all P < .05 by paired t test). Heart rate increased significantly from a baseline mean of 73.2 (SEM = 2.0) beats per minute (bpm) to 78 (SEM = 1.9) bpm within 5 min of the first puff and remained elevated during the ad lib period. The number of puffs during the 1-hr ad lib period ranged from 4 to 76 (M = 46.6, N = 7). Figure 1. Top panel: M (��1 SEM) plasma nicotine (assay��s limit of quantitation = 2 ng/ml; Breland, Kleykamp, & Eissenberg, 2006) levels at baseline (?5) and during the 10-puff and 1-hr ad lib puffing periods.

Filled symbols indicate … VAS ratings of ��Anxious�� were elevated at baseline (M = 13.9, SEM = 4.5), were significantly reduced following the 10-puff (M = 2.8, SEM = 2.5) and ad lib (M = 0.9, SEM = 0.6) periods, and returned to baseline levels after the rest period (M = 12.4, SEM = 4). VAS ratings of ��Restlessness�� were elevated at baseline (M = 26, SEM = 9), were significantly reduced following the ad lib period (M = 4.8, SEM = 4), and increased following the rest period (M = 8.8, SEM = 4) (see Figure 1). Similarly QSU Factor 1 (intention to smoke) scores were elevated at baseline (M = 21, SEM = 2.7), were significantly reduced following the ad lib puffing period (M = 5.6, SEM = 1.

9), and returned to baseline levels after the rest period (M = 18.3, SEM = 2.2). Positive direct effects of EC administration were also observed. VAS ratings of Did the EC help you ��Feel awake,�� ��Calm you down,�� and ��Concentrate�� as well as Was the EC ��Pleasant�� and ��Satisfying�� and Did the EC ��Reduce your hunger for food�� and ��Taste Drug_discovery Good�� increased significantly following the 10-puff period, peaked following the ad lib period, and decreased after the rest period.