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MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.

MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.

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MedlinePlus at a Glance

  • Offers information on health topics, human genetics, medical tests, medications, dietary supplements, and healthy recipes.
  • Sourced from more than 1,600 selected organizations.
  • Provides 40,000 links to authoritative health information in English and 18,000 links to information in Spanish.
  • In 2018, 277 million users viewed MedlinePlus more than 700 million times.

E-Cigarettes

E-cigarettes, or electronic cigarettes, are battery-operated smoking devices. They often look like cigarettes, but work differently. Using an e-cigarette is called vaping. The user puffs on the mouthpiece of a cartridge. This causes a vaporizer to heat the liquid inside the cartridge. The liquid contains nicotine, flavorings, and other chemicals. The heated liquid turns into the vapor that is inhaled.

Some people think that e-cigarettes are safer than cigarettes, and that they can be used to help people quit smoking. But not much is known about the health risks of using them, or whether they do help people quit smoking. However we do know about some dangers of e-cigarettes:

  • They contain nicotine, which is addictive
  • They contain other potentially harmful chemicals
  • There is a link between e-cigarette use and tobacco cigarette use in teens
  • The liquid in e-cigarettes can cause nicotine poisoning if someone drinks, sniffs, or touches it

NIH: National Institute on Drug Abuse