Common Triggers

For people with Mast Cell Activation Syndrome (MCAS), everyday exposures can sometimes lead to sudden and unpredictable reactions. Mast cells are immune cells designed to protect the body, but in MCAS, they release chemical mediators (like histamine) too easily — often in response to triggers that wouldn’t normally cause problems.

Living with Mast Cell Activation Syndrome (MCAS) means that everyday situations can sometimes cause sudden and unexpected symptoms. This happens because mast cells — the immune cells responsible for defending your body — can release chemicals too easily in response to certain triggers.

These triggers vary from person to person, but understanding your unique triggers can make a huge difference in managing symptoms and improving quality of life.