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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.

Hearing Aids

A hearing aid is a small electronic device that you wear in or behind your ear. It makes some sounds louder. A hearing aid can help people hear more in both quiet and noisy situations.

Hearing aids help people who have hearing loss from damage to the small sensory cells in the inner ear. The damage can occur as a result of disease, aging, or injury from noise or certain medicines.

There are different types of hearing aids. They differ by size, their placement on or inside the ear, and how much they amplify sound. The hearing aid that will work best for you depends on what kind of hearing loss you have and how severe it is.

If you think that you need a hearing aid, you have two different options:

  • Over-the-counter (OTC) hearing aids, which you can buy directly. You don't have to get a hearing exam from a healthcare professional first. OTC hearing aids are for adults who have mild to moderate hearing loss.
  • Prescription hearing aids, which you get from an audiologist (a health professional who specializes in hearing and balance disorders). The audiologist will program the hearing aids, based on how severe your hearing loss is. You may need prescription hearing aids or other devices if you have significant or complicated hearing loss.

NIH: National Institute of Deafness and Communication Disorders