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E-cigarettes and E-hookahs

Electronic cigarettes; Electronic hookahs; Vaping; Vape pens; Mods; Pod-Mods; Electronic nicotine delivery systems; Smoking - electronic cigarettes

Electronic cigarettes (e-cigarettes), electronic hookahs (e-hookahs), and vape pens allow the user to inhale a vapor that may contain nicotine as well as flavorings, solvents, and other chemicals. E-cigarettes and e-hookahs come in many shapes, including cigarettes, pipes, pens, USB sticks, cartridges, and refillable tanks, pods, and mods.

There is evidence that some of these products are associated with significant lung injury and death.

I Would Like to Learn About:

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.

E-cigarettes and other devices also may be sold for use with tetrahydrocannabinol (THC) and cannabinoid (CBD) oils. THC is the component in marijuana that produces the "high."


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

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.

As of February 2020, nearly 3,000 people were hospitalized due to lung injury from the use of e-cigarettes and other devices. Some people even died. This outbreak was linked to THC-containing e-cigarettes and other devices that included the additive vitamin E acetate. For this reason, the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) make the following recommendations:

Other safety concerns include:

E-cigarettes and Children

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

More Studies are Needed

There is emerging information about e-cigarettes to suggest they are 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:

When to Call the Doctor

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


Centers for Disease Control and Prevention website. Outbreak of lung injury associated with the use of e-cigarette, or vaping, products. Updated February 25, 2020. Accessed September 15, 2022.

Gotts JE, Jordt SE, McConnell R, Tarran R. What are the respiratory effects of e-cigarettes? BMJ. 2019; 366:l5275. PMID: 31570493

Schier JG, Meiman JG, Layden J, et al; CDC 2019 Lung Injury Response Group. Severe pulmonary disease associated with electronic-cigarette-product use - interim guidance. MMWR Morb Mortal Wkly Rep. 2019;68(36):787-790. PMID: 31513561

US Food and Drug Administration website. E-cigarettes, vapes, and other electronic nicotine delivery systems (ENDS). Updated June 29, 2022. Accessed September 15, 2022.

US Food and Drug Administration website. Lung injuries associated with use of vaping products. Updated April 13, 2020. Accessed September 15, 2022.


Review Date: 5/12/2022  

Reviewed By: Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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