Image: Hope for sufferers

Scott Fisher is running 27 marathons in 27 days to raise funds for Mast Cell Action. 


Visit Scott's justgiving page


Image: Patient's Story

Learn more about our Casper storybook


We have developed a series of wellbeing resources  available to download for free


Welcome to Mast Cell Action

Mast Cell Action was founded in 2016 to offer support to the mast cell disease community, their families, doctors and researchers. To raise awareness of disorders resulting from mast cell activation, increase vital research in this area and strive for better diagnostics and treatment.

Mast Cell Activation Syndrome (MCAS) forms part of a spectrum of mast cell disorders caused by the abnormal proliferation, accumulation, function and/or activation of mast cells. It causes a wide range of unpleasant, frequently debilitating allergic and inflammatory symptoms in many different systems of the body.

People with MCAS can react to a wide range of triggers and potentiating factors including foods, chemicals, drugs, fragrances, temperature, exercise, stress, hormonal fluctuations and infection.

The onset of MCAS can be unpredictable, affecting both children and adults, and presents with a wide range of symptoms in multiple body systems, ranging from hives and rashes, respiratory problems, syncope, gastrointestinal pain, diarrhoea, reflux, neurological problems including anxiety and brain fog, bone pain, and anaphylaxis.

The complex, multisystem nature of MCAS can make gaining a diagnosis particularly challenging. The ability to gain a diagnosis is also negatively impacted by a lack of universally accepted diagnostic criteria and access to diagnostic biomarkers.

There is an urgent need to give a voice to patients, support doctors and researchers, and inform policy-makers about this widely under-recognised condition.

With your support, we feel confident that we can make a substantial difference to the lives of MCAS sufferers and their families.

Our mission


Our Mission:


We believe that everyone suffering from MCAS deserves to have their symptoms acknowledged and experiences listened to, to achieve a correct diagnosis, and to receive the medical care and support that they need.

Logo: Genetic Alliance UK

Mast Cell Action is a member of the Genetic Alliance.

Become a friend

Sign up to become a Friend of Mast Cell Action so we can keep you up to date on our progress and on how to get involved in our latest campaigns and initiatives. Please click on Data Protection at the bottom of the page to see our Data Protection Information.

Become a friend


Mast Cell Action relies entirely on the generosity of people like you. Please make a donation now and together we can make a difference for sufferers of MCAS.

Make a donation