MedlinePlus is an online health information resource for patients and their families and friends.
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).
Our mission is to present high-quality, relevant health and wellness information that is trusted, easy to understand, and free of advertising, in both English and Spanish. Anywhere, anytime, on any device—for free.
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