Chronic Fatigue Syndrome

Chronic Fatigue Syndrome

Chronic fatigue syndrome (CFS) is a complicated disorder characterized by extreme fatigue that can’t be explained by any underlying medical condition. The fatigue may worsen with physical or mental activity, but doesn’t improve with rest.

This condition is also known as systemic exertion intolerance disease (SEID) or myalgic encephalomyelitis (ME). Sometimes it’s abbreviated as ME/CFS.(Information from Mayo Clinic)

 Typically, for an official diagnosis of CFS, an individual must have been sick for six (6) or more months with fatigue severe enough to reduce the individuals activity level by at least 50% and at least four of the following symptoms: impairment in short-term memory or concentration, sore throat, tender lymph nodes, muscle or multi-joint pain without swelling or redness, headaches, unrefreshing sleep, and post-exertional malaise. Physicians must rule out other causes of the symptoms.


International Association for Chronic Fatigue Syndrome (IACFS/ME)
to promote, stimulate and coordinate the exchange of ideas related to CFS, ME and fibromyalgia (FM) research, patient care and treatment.

The International Association for CFS/ME

ATTN: Dr. Fred Friedberg, IACFS/ME

P.O. Box 583

Stony Brook, NY 11790

Voice Mail : 301-634-7701
Online Membership Form

CFIDS Self Help
a non-profit organization offering low-cost online self-help courses and other resources for people affected by Chronic Fatigue Syndrome (CFS) and fibromyalgia (FM).
CFIDS & Fibromyalgia Self-Help Program
777 San Antonio Rd. #121
Palo Alto, CA 94303

Massachusetts CFIDS/FM Association
works to educate health-care providers and the general public regarding these often severely-disabling physical illnesses.
PO Box 690305
Quincy, MA 02269-0305
Information Line: 617-471-5559 (Call for local support listing)
Contact Form

National CFIDS Foundation
Founded in 1997 by two 14 year CFIDS (Chronic Fatigue Immune Dysfunction Syndrome) advocates, the goals of the Foundation are to help fund medical research to find a cause, expedite treatments and eventually a cure for this devastating disease. The NCF also strives to provide information, education, and support to those people who have CFIDS (also known as chronic fatigue syndrome (CFS), myalgic encephalomyelitis (ME) and many other names) — as well as related illnesses such as Gulf War Illness (GWI) and Multiple Chemical Sensitivities (MCS).
103 Aletha Road
Needham, MA 02492
Phone: 781-449-3535
Fax: 781-449-8606
Newsletter: The National Forum

 Solve ME/CFS Initiative

The Solve ME/CFS Initiative (SMCI) is a non-profit disease organization that works to accelerate the discovery of safe and effective treatments, strives for an aggressive expansion of funding for research that will lead to a cure and seeks to engage the entire ME/CFS community in research. Through scientific research and advocacy, SMCI serves patients and researchers alike, serving as an information center for the entire ME/CFS community, and enabling SMCI to make an even stronger case for federal government ME/CFS spending, by generating verifiable and large data sets with reliable metrics.
Solve ME/CFS Initiative
350 N Glendale Avenue
Suite B #368
Glendale, CA 91206
Phone: 704-364-0016
General Requests:

Other Information:

Chronic Fatigue Syndrome – US National Library of Medicine

Center for Disease Control – Chronic Fatigue Syndrome

Additional Resources found on our Fibromyalgia Fact Sheet

Fact Sheet last updated on: 9/16/2021


Disclaimer:  INDEX is pleased to provide you this information. Please note, this information is not comprehensive, nor is it intended to take the place of professional advice. We encourage you to check other resources of such information. No endorsement by the University of Massachusetts Chan Medical School,, INDEX, or affiliates, should be inferred. We reserve the right to remove, to modify, or to add any information at any time, for any reason, and without notice.

Any information you may provide to update or further complete this information would be appreciated. Please contact us with comments. We appreciate your help.