#126 - Management of mast cell activation syndrome - A clinical yardstick

Mast cell activation syndrome (MCAS) is a confusing and often misunderstood condition. If you’ve ever wondered about MCAS symptoms, serum tryptase testing, or how treatments like antihistamines, sodium cromolyn, and even omalizumab fit in, this episode is here to help.

We review the findings from “Management of indolent mastocytosis and mast cell activation syndrome - A clinical yardstick,” published in June 2025 in The Annals of Allergy, Asthma & Immunology. Because the paper covers both diseases, we’ve split it into two parts. This episode focuses on mast cell activation syndrome (MCAS).

GET THE INFOGRAPHIC - summary of this episode

What we cover in our episode about mast cell activation syndrome:

• Yardsticks explained: Why the ACAAI uses yardsticks as practical, interim guidelines before full consensus statements are available.
• Classifying mast cell disorders: Primary (clonal), secondary (allergy/autoimmune), and idiopathic (MCAS).
• MCAS diagnosis criteria: Symptoms in 2 or more organ systems, objective evidence (serum tryptase or urinary metabolites tests), and positive response to therapy.
• Treatment strategies: Include trigger avoidance, H1/H2 antihistamines, leukotriene blockers, mast cell stabilizers (such as cromolyn and aspirin), off-label biologics like omalizumab, and epinephrine.
• Neuropsychiatric symptoms: Brain fog, anxiety, and depression are common and require multidisciplinary management.

The Itch Review, hosted by Dr. Gupta, Kortney, and Dr. Blaiss, explores allergy and immunology studies, breaking down complex research in conversations accessible to clinicians, patients, and caregivers. Each episode provides key insights from journal articles and includes a one-page infographic in the show notes for easy reference.

Made in partnership with The Allergy & Asthma Network.

Thanks to Blueprint Medicines for sponsoring today’s episode.

This podcast is for informational purposes only and does not substitute professional medical advice. Always consult with your healthcare provider for any medical concerns.