Question to the Department of Health and Social Care:

To ask the Secretary of State for Health and Social Care, what guidance is provided to NHS Trusts on the diagnosis and management of Mast Cell Activation Syndrome in the absence of traditional allergy markers.

There is currently no National Institute for Health and Care Excellence (NICE) clinical guideline specifically covering the diagnosis and management of mast cell activation syndrome (MCAS). In the absence of condition‑specific national guidance, clinicians are expected to use their professional judgement, drawing on the available evidence, specialist advice, and relevant NICE guidance for related conditions and symptoms.

Care for people with suspected or confirmed MCAS is typically delivered through established allergy, immunology and other relevant specialist services, with management focused on individual symptoms and clinical need. National Health Service trusts are expected to follow recognised standards of evidence‑based practice, work within agreed local pathways, and involve multidisciplinary teams where appropriate, particularly given the complex and multi‑system nature of the condition.

The Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Final Delivery Plan will support improvements for people with overlapping conditions such as MCAS by promoting more coordinated, person-centred care across primary, community and specialist services. Through actions to improve clinical education, strengthen multidisciplinary working, and develop clearer local pathways aligned with NICE guidance, the plan aims to ensure that patients with complex, multi-system presentations are assessed holistically and have their symptoms managed more effectively. While commissioning decisions remain local, this approach will help services better recognise co-existing conditions and provide more joined-up care for those with overlapping needs.