The words “syndrome” and “disease” are often used interchangeably, but they have some important differences.

The classification, though, has no bearing on whether they’re real illnesses or how serious they are. It’s simply a matter of how well they’re understood.

This article examines the differences between a syndrome and a disease and provides examples of both.

Nomad / Getty Images

Doctor showing digital tablet to patient

What Is a Syndrome?

The definition of a syndrome is pretty straightforward:

In typical medical usage, a syndrome often doesn’t have an understood cause, course, or underlying process. This generally means treatments are lacking and there’s no known cure.

When doctors designate something a syndrome, they’re essentially saying, “We recognize this cluster of symptoms but we don’t yet know what’s going on.”

That doesn’t mean the symptoms aren’t real or aren’t serious, it just means medical science hasn’t yet determined why they’re happening.

Common Syndromes

Examples of syndromes and their primary symptoms are:

Many conditions start out as syndromes and are then re-classified as a disease once more is known about them. If the name of the illness contains the word syndrome, it may or may not be changed.

What Is a Disease?

The definition of disease is a little more complicated than that of syndrome. You can find several, incuding:

The second definition especially doesn’t seem to do a good job of separating a disease from a syndrome. In common medical usage, though, a disease is generally considered to have:

Common Diseases

Examples of disease and their causes are:

When researchers re-classify a syndrome as a disease, sometimes the name is changed and sometimes it’s not. For example, AIDS is still in use even though the S stands for syndrome and it’s now considered a disease. When names are changed, it can take time for the new name to gain widespread use.

How an Organic Disease Differs From a Functional Disorder

Summary

A syndrome is a group of signs and symptoms that are known to go together but don’t have a clear cause, course, or treatment path.

A disease is a disorder that affects how your body functions and is more likely to have a known cause, a distinct course, and established treatments.

If you’re diagnosed with a syndrome, you may run into people who don’t think it’s serious or “real” because it’s not a disease. This isn’t the case. It really just means that medical science hasn’t figured it out yet.

Frequently Asked Questions

Medically speaking, a condition is anydisease, disorder, syndrome, or tissue abnormality. Some definitions of condition exclude mental disorders.

21 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

National Institutes of Health, National Cancer Institute.Syndrome.

University of Utah: U Health.What are syndromes?

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus.Metabolic syndrome.

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus.Fibromyalgia.

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus.Restless legs.

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus.Irritable bowel syndrome.

Jafri MS.Mechanisms of myofascial pain.Int Sch Res Notices. 2014;523924. doi:10.1155/2014/523924

National Vulvodynia Association.What is vulvodynia?

National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases.Interstitial cystitis (painful bladder syndrome).

Johns Hopkins Medicine.Multiple chemical sensitivity.

Dictionary.com.Disease.

Centers for Disease Control and Prevention.Chickenpox (varicella).

Centers for Disease Control and Prevention.Types of influenza viruses.

Centers for Disease Control and Prevention.Cold versus flu.

Centers for Disease Control and Prevention.About infectious mononucleosis (Mono).

World Health Organization.Coronavirus disease (COVID-19).

National Health Service.Causes: Parkinson’s disease.

National Institutes of Health, U.S. National Library of Medicine: MedlinePlus.Autoimmune disorders.

National Institutes of Health, National Cancer Institute.What is cancer?

Pallipedia.Medical condition.

Meet Our Medical Expert Board

Share Feedback

Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit

Was this page helpful?

Thanks for your feedback!

What is your feedback?OtherHelpfulReport an ErrorSubmit

What is your feedback?