Understanding the Link Between MCAS and POTS: Root Causes and Natural Healing Strategies

If you’ve been dealing with dizziness, heart palpitations, fatigue, or sudden allergic-like reactions to foods, smells, or supplements, you may have heard the terms MCAS and POTS. These two syndromes are increasingly recognized in people with complex, chronic health conditions—and they’re more connected than you might think.

Let’s unpack the relationship between Mast Cell Activation Syndrome (MCAS) and Postural Orthostatic Tachycardia Syndrome (POTS), and explore natural treatment options that can help calm your nervous system and support long-term healing.

What is MCAS?

Mast Cell Activation Syndrome occurs when mast cells—a type of immune cell—become overactive and release excessive amounts of histamine and other inflammatory chemicals. This leads to symptoms like:

• Flushing, hives, or itching

• Nasal congestion or post-nasal drip

• GI issues (bloating, diarrhea, nausea)

• Brain fog or anxiety

• Sensitivity to foods, supplements, smells, and chemicals

What is POTS?

Postural Orthostatic Tachycardia Syndrome is a form of dysautonomia, or dysfunction of the autonomic nervous system. It’s defined by a heart rate increase of ≥30 bpm (or ≥40 bpm in teens) within 10 minutes of standing. Common symptoms include:

• Dizziness or lightheadedness when standing

• Racing heart or palpitations

• Fatigue or “crashing” after activity

• Brain fog

• Exercise intolerance

How Are MCAS and POTS Connected?

Both conditions often co-occur in people with autoimmunity, mold toxicity, Lyme disease, EDS (Ehlers-Danlos Syndrome), or long COVID. The connection lies in nervous system dysregulation and immune hypersensitivity.

• MCAS may worsen POTS symptoms by releasing histamine, which dilates blood vessels and lowers blood pressure.

• POTS can trigger stress responses that aggravate mast cell instability.

Essentially, both syndromes reflect a body stuck in “fight or flight” mode with poor tolerance to stimuli or stressors.

Natural Treatment Options

While medications like antihistamines and beta blockers can be helpful, many patients respond well to a holistic, functional medicine approach that targets the root causes. Here are some natural strategies:

1. Nervous System Regulation (Limbic Retraining)

• Programs like DNRS, Gupta Program, or Primal Trust can retrain the brain to stop overreacting to benign stimuli.

• Daily practice helps desensitize the overactive limbic and autonomic nervous systems.

2. Low Histamine Diet

• Temporarily avoid high-histamine foods (fermented foods, leftovers, aged cheeses, alcohol).

• Add DAO-supportive nutrients like vitamin C, copper, and B6.

3. Mast Cell Stabilizers

• Natural options include:

  • Quercetin

  • Luteolin

  • Stinging Nettle

  • Vitamin C

  • Butterbur

• Start low and slow to avoid flare-ups.

4. Electrolyte and Volume Support for POTS

• Increase fluids (2.5–3L/day)

• Add electrolytes (LMNT, Nuun, or homemade mixes)

• Consider salt-loading under guidance

5. MCAS/POTS-Friendly Exercise

• Start with recumbent or resistance training (rowing, biking, pilates)

• Avoid intense cardio at first—build up slowly to improve blood flow and vagal tone

6. Address Root Causes

• Mold toxicity → Test with urine mycotoxins, treat with binders and avoidance

• Lyme and co-infections → Consider herbal antimicrobials or low dose immunotherapy (LDI)

• Gut dysbiosis → Heal leaky gut, support microbiome

• Hormone imbalances → Especially cortisol, estrogen, and aldosterone

Final Thoughts

MCAS and POTS can feel overwhelming, but with the right tools and a systems-based approach, the body can heal. By calming the immune system, supporting the nervous system, and addressing root causes, many people regain their energy, focus, and freedom.

If you or a loved one is struggling with symptoms of MCAS and POTS, working with a functional medicine provider, like Xenia, who understands the big picture can make all the difference. Xenia is serving patients in Austin, Dallas, Houston, San Antoni, and the entire State of Texas.

Your Functional Med NP,

Xenia