Is MCAS connected to endometriosis?

Yes, there appears to be an evolving connection, but it’s not as simple as equating endometriosis with MCAS. Current research most strongly supports that mast cells (the immune cells involved in allergic-type reactions) are often increased and more activated in and around endometriosis lesions, where they tend to cluster near nerves and blood vessels. When mast cells release mediators like histamine and other inflammatory signals, they can irritate pain-sensing nerves, promote nerve growth, and help sustain inflammation. This is one plausible reason endometriosis pain can feel burning, stabbing, widespread, or unusually persistent.

MCAS, though, is a systemic syndrome, meaning it can cause multi-system flares, such as flushing/itching, GI upset, shortness of breath, dizziness, or fast heart rate, and may be triggered by stress, hormones, foods, or environmental exposures. Some people with endometriosis also have MCAS-like symptoms, and in those cases mast-cell biology may be amplifying pelvic pain and lowering the threshold for flares across the body. If this overlap sounds familiar, our team can help you sort out what’s likely driven by endometriosis lesions themselves (including whether excision surgery may be part of your plan) versus broader mast-cell-type sensitivity that may need coordinated perioperative and long-term management.