Rare Diseases
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
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
Questions for your care team
General prompts to help prepare for your appointment.
- How does this information apply to my situation?
- Which symptoms or results need evaluation?
- Which tests are useful, and what can they tell us?
- What care options, benefits, and risks should we discuss?
- When should I seek urgent help, and whom should I call?
- When is follow-up, and how will we know whether the plan is working?
For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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