Living with a mast cell disease can affect almost every part of someone's life, yet the impact is often invisible to others.

This International Mastocytosis and Mast Cell Diseases Awareness Day, we're joining organisations and communities around the world to raise awareness, share experiences and help more people understand what life with a mast cell disease can really be like.

The theme for 2026 is Unnoticed. Unmistakable. Because while symptoms may go unnoticed by those around us, their impact on the person experiencing them can be unmistakable.

Why awareness matters

Mast cell diseases, including Mast Cell Activation Syndrome (MCAS) and mastocytosis, can cause a wide range of symptoms affecting different parts of the body. For some people, symptoms fluctuate from day to day. For others, they can be persistent, debilitating and life-changing. People living with these conditions may face difficulties accessing diagnosis, finding appropriate healthcare and having their symptoms understood or taken seriously. The effects can reach far beyond physical symptoms, affecting education, employment, relationships, family life and emotional wellbeing.

The effects can reach far beyond physical symptoms, affecting education, employment, relationships, family life and emotional wellbeing.

Greater awareness can help change this.

At Mast Cell Action, we believe everyone affected by MCAS deserves to be listened to, understood and supported to live as well as possible. Awareness Day is an opportunity to bring our community together, challenge misconceptions and encourage greater understanding among healthcare professionals, families, employers and the wider public.

Get involved this Awareness Day

There are lots of ways to get involved with this year's Awareness Day.

Help more people understand mast cell diseases by sharing the international campaign's posts and resources with friends, family and your wider community. The campaign has ready-made social media graphics and messages you can download and share. Download the campaign resources here.

Tell your story. What do you wish more people understood about living with MCAS or another mast cell disease? Sharing your experience can help others understand the challenges that aren't always visible. You could write a social media post, share a photograph or record a short video. You can share as much or as little as you feel comfortable with. The international campaign has created a Canva template to help you create your own awareness post, along with guidance on sharing your story.

Download an Awareness Day poster to display in your workplace, school, university, healthcare setting or community space.

Awareness is about more than recognising a name. It's about understanding how MCAS can affect someone's everyday life and why appropriate support matters.

You could share Mast Cell Action's information and resources with someone who wants to learn more, whether that's a friend, family member, employer or healthcare professional.

Even one conversation can help build greater understanding.

Together, we can make a difference.