The Documented POTS and Mast Cell Overlap, the hEDS Triad, and Where Physical Therapy Supports
Part of the Femina PT POTS & Orthostatic Intolerance Series | Complete Guide: POTS & Orthostatic Intolerance Physical Therapy in Los Angeles
If your POTS comes with flushing, hives, unexplained reactions to foods or scents, or gut symptoms that seem to flare alongside everything else, you may have encountered the term MCAS, mast cell activation syndrome. The POTS-MCAS overlap is an active area of clinical interest, and also one where overstated claims are common. Below we review what the research shows, and where it is mixed or inconclusive.
What the POTS-MCAS overlap involves
Some researchers think mast cell activation may play a role in one form of POTS, a type where the body runs high on adrenaline (a hyperadrenergic type). In a 2005 study, patients with mast cell activation and POTS presented with episodes of flushing, shortness of breath, headache, lightheadedness, and gastrointestinal symptoms, with triggers including prolonged standing, exercise, meals, and the premenstrual phase[1]. In a later cohort of 69 POTS patients, about 42% had additional symptoms not tied to standing (non-orthostatic symptoms), such as migraine, allergic complaints, skin rash, or GI symptoms, together with at least one raised lab marker that suggests mast cell activation (immune cells releasing too many chemicals such as histamine)[2].
To clarify how common this is: in a study of young patients meeting POTS criteria, the share of patients with MCAS ranged from as low as 2% using strict criteria to as high as 87% using looser criteria[3]. That wide range is the key point: the way MCAS is defined is still debated, so prevalence figures should be read with caution, and MCAS is likely both under- and over-diagnosed depending on who is applying which criteria.
This overlap also travels with hypermobility. POTS, hypermobility spectrum disorders/hEDS, and MCAS are frequently discussed together, especially in young women[3][4]. See how the hEDS-POTS side of that triad works.
MCAS is diagnosed and treated by physicians
Diagnosing and treating MCAS, with antihistamines, mast cell stabilizers, and related medicines, is medical care led by an allergist, immunologist, or another physician specialist on your medical team. That 2005 study also cautions that beta-blockers should be used carefully in this subtype[1], which is the kind of medication decision that belongs with your doctor, not your physical therapist. Femina Physical Therapy does not diagnose or treat MCAS.
Where physical therapy fits
What physical therapy contributes is trigger-aware rehabilitation. Because exercise and heat can themselves provoke symptoms in this population[1], the graded exercise approach that is well supported for POTS[5] has to be delivered carefully: paced, mindful of heat, and progressed slowly, so that the therapy which helps your POTS does not set off a flare. We collaborate with the medical team managing the mast cell side. The aim is steady, tolerable progress within limits your body and your physicians define.
✅ This is what evidence-informed care looks like: we tell you what the research shows, what it does not yet show, and why an approach is still worth trying for you. Then we measure whether it is working for your body specifically.
“The key point is the wide range. We read prevalence figures with caution and screen individually.”
📍 Femina Physical Therapy treats POTS and orthostatic intolerance across Los Angeles, with offices in Sherman Oaks, Pasadena, and Beverly Hills. Telehealth and Coaching consultations are available for patients whose symptoms make travel difficult.
FAQ — PEOPLE ALSO ASK
Mast cell activation has been proposed as a contributor to a hyperadrenergic subtype of POTS, and studies document overlapping symptoms such as flushing, gastrointestinal issues, and allergic-type complaints alongside orthostatic intolerance. The association is documented, but the underlying mechanisms are not fully established.
Estimates vary dramatically depending on the diagnostic criteria used, from around 2% under strict consensus criteria to as high as 87% under looser clinical criteria in one study of young patients. Because the definitions are contested, prevalence figures should be interpreted with caution.
No. MCAS is diagnosed and treated medically, typically by an allergist, immunologist, or another physician specialist, using antihistamines and mast cell stabilizers. A physical therapist’s role is to adapt POTS rehabilitation so it avoids triggering flares and to coordinate with the team managing the mast cell condition.
Both exercise and heat are documented triggers in this population, which is why a standard exercise plan can backfire. A paced, temperature-conscious, gradually progressed program lets you get the benefits of conditioning for POTS while minimizing the risk of setting off a mast cell or orthostatic flare.
>> Living with POTS in Los Angeles? Trigger-aware rehabilitation can keep progress steady. Book your evaluation at Femina Physical Therapy.
References (Peer-Reviewed Sources)
[1] (Class C) Shibao C, et al. Hyperadrenergic postural tachycardia syndrome in mast cell activation disorders. Hypertension. 2005;45:385-390. [pubmed.ncbi.nlm.nih.gov/15710782]
[2] (Class C) Mast cell activation disorder and postural orthostatic tachycardia syndrome: a clinical association. J Am Heart Assoc. 2021. [pubmed.ncbi.nlm.nih.gov/34398691]
[3] (Class C) Association of POTS, hypermobility spectrum disorders, and mast cell activation syndrome in young patients; prevalence and overlap depend on the definition. (PMC12063504) [ncbi.nlm.nih.gov/pmc/articles/PMC12063504]
[4] (Class C) Symptomatic Joint Hypermobility: the hypermobile type of Ehlers-Danlos syndrome and the hypermobility spectrum disorders. 2019. [pubmed.ncbi.nlm.nih.gov/31582002]
[5] (Class A) Fu Q, VanGundy TB, Shibata S, Auchus RJ, Williams GH, Levine BD. Exercise training versus propranolol in the treatment of the postural orthostatic tachycardia syndrome. Hypertension. 2011;58(2):167-175. [pubmed.ncbi.nlm.nih.gov/21690484]
Related Reading: POTS & Orthostatic Intolerance at Femina Physical Therapy
→ The hEDS-POTS overlap: hypermobility and dysautonomia together
→ Hydration, sodium, and compression: the non-exercise foundations
→ Complete Guide: POTS & Orthostatic Intolerance Physical Therapy in Los Angeles (Pillar)
Medical disclaimer: This article is for informational purposes only and is not intended as medical advice. Always consult your medical doctor before beginning this or any program that may affect your health. Reading this article does not create a patient relationship with Femina Physical Therapy.