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Nancy A Rigotti, MD
Sara Kalkhoran, MD, MAS
Section Editors
James K Stoller, MD, MS
Mark D Aronson, MD
Deputy Editor
Judith A Melin, MA, MD, FACP


Electronic cigarettes (e-cigarettes) are battery-operated devices that heat a liquid usually containing nicotine, producing a vapor that the user inhales (figure 1) [1]. E-cigarettes entered the market in 2003 in China and entered the United States and European markets in 2006 [2]. In many areas, e-cigarettes entered the market as consumer products without government regulation. Initially produced by small companies, tobacco companies have bought some of these companies and are developing these products [3,4]. They are available both online and in traditional retail outlets.

There is uncertainty about the long-term health effects of e-cigarettes and whether they will help individual tobacco users to stop smoking [5,6]. There are also public health concerns, including concerns about the effect of e-cigarettes on smoking prevalence and their potential use by children as a gateway to subsequently using combustible tobacco products [7].

This topic will provide an overview of e-cigarettes, including information about devices, use, components, adverse health effects, use in smoking cessation, impact on public health, as well as suggestions for patient counseling. An overview of smoking cessation and pharmacotherapies and behavioral therapies for smoking cessation are discussed in detail elsewhere. (See "Overview of smoking cessation management in adults" and "Pharmacotherapy for smoking cessation in adults" and "Behavioral approaches to smoking cessation".)


E-cigarettes consist of a cartridge containing a liquid, an atomizer (vaporization chamber with a heating element), and a battery (figure 1) [4,8].

The user activates the atomizer either by inhaling or by pressing a button, depending on the device characteristics. The atomizer then heats and aerosolizes the liquid in the cartridge, creating a vapor that emulates but is not tobacco smoke. This process simulates the experience of smoking a conventional cigarette, but no combustion occurs. The term "vaping" is used to distinguish the process from smoking a conventional cigarette. The term “dripping” is used to describe a technique in which a couple of drops of the liquid in the e-cigarette cartridge are dripped directly onto the atomizer’s heating element to create a cloud of vapor that can be inhaled [9].

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Literature review current through: Nov 2017. | This topic last updated: Nov 03, 2017.
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