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URL of this page: https://medlineplus.gov/rarediseases.html

Rare Diseases

Summary

A rare disease is one that affects fewer than 200,000 people in the United States. There are nearly 7,000 rare diseases. More than 25 million Americans have one.

Rare diseases:

  • May involve chronic illness, disability, and often premature death
  • Often have no treatment or not very effective treatment
  • Are frequently not diagnosed correctly
  • Are often very complex
  • Are often caused by changes in genes

It can be hard to find a specialist who knows how to treat your rare disease. Disease advocacy groups, rare disease organizations, and genetics clinics may help you to find one.

NIH: National Institutes of Health

Learn More

Clinical Trials

Find an Expert

  • Contact Us From the National Institutes of Health (Genetic and Rare Diseases Information Center)

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.