@drsermedmezher: POV: You Have a POTS+1. Sources- PMID 34398691 chronicals_with_gee on TT Postural Orthostatic Tachycardia Syndrome (POTS) and Mast Cell Activation Syndrome (MCAS) are increasingly recognized by clinicians as frequent co-travelers, often appearing together alongside Ehlers-Danlos Syndrome in what is colloquially known as the "trifecta." Research indicates a staggering overlap between these conditions, with some clinical studies suggesting that up to 66% of patients diagnosed with POTS also meet the diagnostic criteria for MCAS, depending on how strictly those criteria are applied. This intersection is likely due to the fact that mast cells, which are part of the immune system, are often located in close proximity to the nerves of the autonomic nervous system. When mast cells become overactive and "degranulate," they release a cocktail of inflammatory chemicals like histamine that can directly irritate the nerves responsible for regulating heart rate and blood pressure. The clinical presentation of this overlap can be particularly challenging because the symptoms of one often trigger or exacerbate the symptoms of the other. For instance, the release of histamine from mast cells causes systemic vasodilation, a widening of the blood vessels, which makes it harder for the body to return blood to the heart when standing up. This drop in effective blood volume forces the heart to beat faster to compensate, worsening the characteristic tachycardia of POTS. Furthermore, many POTS patients find that their "flares" are triggered by things typically associated with MCAS, such as heat, certain foods, or stress. Because of this high rate of comorbidity, many specialists now advocate for screening POTS patients for mast cell issues, as managing the underlying immune activation can sometimes lead to a significant reduction in autonomic instability. #allergy #pots #mcas

Dr Sermed Mezher MBChB MRes

Open In TikTok:

Region: GB

Saturday 31 January 2026 23:04:50 GMT