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E-cigarettes and E-hookahs


Electronic cigarettes (e-cigarettes) and electronic hookahs (e-hookahs) allow the user to inhale a vapor that may contain nicotine as well as other flavors and chemicals. Many e-cigarettes and hookahs look just like real cigarettes or pipes. But some look like pens or USB memory sticks. Not much is known yet about the benefits and risks of these products.

Alternative Names

Electronic cigarettes; Electronic hookahs; Vaping; Electronic nicotine delivery systems; Smoking - electronic cigarettes

How They Work

There are many types of e-cigarettes and e-hookahs. Most have a battery-operated heating device. When you inhale, the heater turns on and heats a liquid cartridge into a vapor. The cartridge may contain nicotine or other flavors or chemicals. It also contains glycerol or propylene glycol (PEG), which looks like smoke when you exhale. Each cartridge can be used a few times. Cartridges come in many flavors.


The makers of e-cigarettes and e-hookahs market their products for several uses:

  • To use as a safer alternative to tobacco products. The makers claim their products do not contain the harmful chemicals found in regular cigarettes. They say this makes their products safer choices for those who already smoke and don't want to quit.
  • To "smoke" without getting addicted. Consumers can choose cartridges that do not contain nicotine, the addictive substance found in tobacco.
  • To "smoke" in areas where smoking is banned. Since there are not yet bans against e-cigarettes in many places, these products allow smokers to "smoke" in smoke-free areas.
  • To use as a tool to help you quit smoking. Some companies tout their products as a way to quit smoking. More studies are needed to prove this claim.

E-cigarettes have not been fully tested. So it is not yet known if any of these claims are true.

Safety Concerns

Health experts have many concerns about the safety of e-cigarettes and e-hookahs.

  • There is no evidence that shows these products are safe to use over the long term.
  • There are chemicals that can cause cancer in some of the products they tested. One sample contained a toxic ingredient found in antifreeze.
  • The ingredients in e-cigarettes are not labeled, so it is not clear what's in them.
  • It is not known how much nicotine is in each cartridge. The FDA found nicotine in 1 sample that was labeled nicotine-free.
  • It is not known if these devices are a safe or effective way to quit smoking.
  • Non-smokers may start using e-cigarettes because they believe these devices are safe.

E-cigarettes and Children

Many experts also have concerns about the effects of these products on children.

  • These products are sold in flavors that may appeal to children and teens, such as chocolate and key lime pie. This could lead to more nicotine addiction in children.
  • Teens who use e-cigarettes may be more likely to take up smoking regular cigarettes.

More Studies are Needed

There is not enough information about e-cigarettes to know if they are safe or harmful. Until more is known about their long-term effects, the FDA and the American Cancer Association recommend steering clear of these devices.

If you are trying to quit smoking, your best bet is to use FDA-approved smoking cessation aids. These include:

  • Nicotine gum
  • Lozenges
  • Skin patches
  • Nasal spray and oral inhaled products

When to Call the Doctor

If you need more help quitting, talk with your provider.


Benowitz NL, Brunetta PG. Smoking hazards and cessation. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 46.

Callahan-Lyon P. Electronic cigarettes: human health effects. Tob Control. 2014;23(Suppl 2):ii36-ii40. PMID: 24732161

Primack BA, Soneji S, Stoolmiller M, Fine MJ, Sargent JD. Progression to traditional cigarette smoking after electronic cigarette use among US adolescents and young adults. JAMA Pediatr. 2015;169:1018-1023. PMID: 26348249

US Food and Drug Administration. Vaporizers, E-Cigarettes, and other Electronic Nicotine Delivery Systems (ENDS). Updated June 3, 2016. Accessed June 27, 2016.

Review Date:5/21/2016
Reviewed By:Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

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