National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Mast cell activation syndrome


Other Names:
MCAS
Mast cell activation syndrome (MCAS), is an immunological condition in which mast cells mistakenly release too many chemical mediators, resulting in several chronic symptoms involving the skin, gastrointestinal tract, heart, respiratory, and neurologic systems. Mast cells are present throughout most of our bodies and secrete different chemicals during allergic reactions. Symptoms include episodes of abdominal pain, cramping, diarrhea, flushing, itching, wheezing, coughing, lightheadedness and potential problems with "brain fog" or other difficulties with memory.[1][2][3] The cause of MCAS is unknown. Treatment includes several combinations of medications like anti-histamines and mast cell stabilizers.[4][2]
Last updated: 11/21/2016

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Mast cell activation syndrome. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

Selected Full-Text Journal Articles

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  1. Theoharides TC, Valent P, and Akin C. Mast Cells, Mastocytosis, and Related Disorders. N Engl J Med. July 9, 2015; 373(2):163-172. https://www.ncbi.nlm.nih.gov/pubmed/26154789.
  2. Akin C. Mast cell activation disorders. UpToDate. December, 2014; http://www.uptodate.com/contents/mast-cell-activation-disorders.
  3. Akin C. Mast Cell Activation Syndrome: Proposed Diagnostic Criteria. J Allergy Clin Immunol. December, 2010; 126(6):1099–104. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3753019/.
  4. Soderberg ML. The Mast Cell Activation Syndrome: A Mini Review. MOJ Immunol. 2014; 2(1):http://medcraveonline.com/MOJI/MOJI-02-00032.pdf.