Effects of e-Cigarettes on Nicotine Withdrawal

Nicotine withdrawal symptoms (e.g., increased negative affect, decreased positive affect,
cigarette craving) are a core component of cigarette dependence that emerge upon the absence
of nicotine administration, maintaining cigarette smoking and inhibiting cessation efforts.
The use of electronic cigarettes (e-cigarettes) has increased dramatically in recent years,
with studies demonstrating that e-cigarettes can reduce nicotine withdrawal symptoms during
acute cigarette abstinence. E-cigarettes with flavorings that simulate the sweet taste of
fruit, candy and other sugary foods and beverages are widely available, commonly used and are
frequently cited as a reason for the persistent use of e-cigarettes. During nicotine
withdrawal, sweet flavors have been shown to reduce nicotine withdrawal symptoms.
Additionally, a recent USC TCORS (Tobacco Center of Regulatory Science) administrative
supplement study conducted at the University of Southern California (USC) Health, Emotion,
and Addiction Laboratory (USC-HEAL) found that sweet-flavored solutions enhanced the appeal
of e-cigarettes, independent of nicotine. However, the impact of e-cigarette flavorings on
nicotine withdrawal symptoms is currently unknown. This behavioral pharmacology laboratory
experiment will assess whether sweet (vs. non-sweet) flavored e-cigarette solutions reduce
tobacco withdrawal symptoms and motivation to smoke among 40 smokers interested in trying
e-cigarettes (for the first time) following 16-hours of nicotine abstinence. At each visit,
participants will complete a standardized e-cigarette administration procedure, as developed
in our prior work, in which flavor will be manipulated in a double-blind, cross-over,
counterbalanced design. Following the e-cigarette administration, participants will complete:
1) self-report measures of nicotine withdrawal symptoms; 2) physiological measurements and 3)
a behavioral task that measures participants' ability to resist the desire to resume smoking
under conditions in which it is advantageous to remain abstinent (i.e., monetary payment for
each successive 5-min increment in which smoking is delayed). The study's experimental design
will provide evidence of the causal effects of e-cigarette flavorings on a putatively
critical factor for determining whether smokers continue e-cigarette use after initial
trial—the ability of a product to suppress withdrawal and motivation to smoke during periods
of tobacco deprivation.

Inclusion Criteria:

1. 21 years of age or older;

2. Daily cigarette smoking for at least the past two years;

3. Currently smoke > 10 cig/day;

4. Interest in trying e-cigarettes;

5. report primarily smoking non-mentholated cigarettes.

Exclusion Criteria:

1. Current use of medications that impact withdrawal or smoking (e.g., bupropion,
varenicline, nicotine replacement, anti-depressants, anxiolytics);

2. Prior use of e-cigarettes (i.e., self-report > 10 puffs lifetime, use on more than two
occasions, purchased own device);

3. breath carbon monoxide (CO) < 10 at intake;

4. pregnancy/breastfeeding; and

5. daily use of other tobacco products (e.g., hookah, cigars).