- Category : Histamine Intolerance / MCAS
Postural Orthostatic Tachycardia Syndrome (POTS) and Mast Cell Activation Syndrome (MCAS) are two medical conditions that have gained increasing attention in recent years. While they are distinct disorders, there is growing evidence suggesting a significant connection between both POTS and MCAS (*). In today’s article. I’ll explain how POTS and MCAS are connected, how the nerve system affects POTS and MCAS, some of the root causes or triggers in POTS and MCAS. Finally, I will explain how Functional Medicine can help people who suffer from POTS and MCAS.
What is POTS
Postural Orthostatic Tachycardia Syndrome (POTS) is a condition that affects the autonomic nervous system (ANS), which is responsible for regulating involuntary bodily functions like heart rate, blood pressure, and digestion. Most patients with POTS are young women, with recent estimates suggesting a 94% female predominance. Symptoms often occur after an acute event. This might include things like a viral infection, vaccination, physical trauma, surgery, and even pregnancy. Research supports and suggests that there is an immune-mediated process at play.
POTS is characterized by a significant increase in heart rate when moving from lying down to a standing position, along with a range of other symptoms that can include dizziness, lightheadedness, and fatigue.
Histamine Intolerance/Mast Cell Activation Syndrome (MCAS)
Histamine intolerance and MCAS involve the inappropriate activation of mast cells, which are essential to the body’s immune response. When mast cells are activated abnormally, they release excessive amounts of histamine, prostaglandins, and tryptase.
These inflammatory mediators can lead to a variety of symptoms, such as itching, skin rashes, flushing, Hives, gastrointestinal issues, respiratory problems, cardiovascular symptoms, abdominal pain, headaches, and more.
Both POTS and Histamine Intolerance/MCAS can create a complex clinical picture. Let’s take a look at how POTS and MCAS are connected.
How POTS and MCAS Are Connected
Mast Cell Activation Syndrome (MCAS) and Postural Orthostatic Tachycardia Syndrome (POTS) while they are distinct disorders, are conditions that are often found together in what appears to be a significant subset of patients. (*)(*),(*)(*)
The excessive release of histamine and other inflammatory mediators from mast cells in MCAS can impact the cardiovascular system, the nerve systems, and the gastrointestinal system all of which affect patients who have POTS.
Both POTS and MCAS share many of the same symptoms- This is partly due to the involvement of the nervous system, as well as the shared inflammatory processes, gastrointestinal issues, and various comorbidities.
1. Shared Symptoms: Both POTS and MCAS are connected by the many shared symptoms. POTS and MCAS can both cause symptoms such as fatigue, brain fog, palpitations, and dizziness. This overlap can sometimes make it difficult to distinguish between the two. Even with testing, it can be difficult to have a hard “diagnosis”
2. Autonomic Nervous System Involvement: Another way POTS and MCAS are connected is that in both conditions we have dysregulation of the autonomic nervous system (ANS). In POTS, this dysregulation primarily affects heart rate and blood pressure control. People with POTS may experience visual disturbances like blurred vision or seeing spots, especially during changes in position.
Another prevalent symptom is “brain fog,” a sensation of mental cloudiness that makes it difficult to concentrate and remember things, significantly affecting cognitive function. Fatigue is also common, manifesting as persistent tiredness that impacts daily activities and alertness. Additionally, people with POTS may experience visual disturbances like blurred vision or seeing spots, especially during changes in position.
Mast cell activation can have multifaceted effects on the nervous system, contributing to a wide range of neurological and psychological symptoms. This can result in symptoms like abnormal heart rate, blood pressure fluctuations, and gastrointestinal dysmotility.
Mast cells release histamine and other substances that can influence neurotransmitter function. This can impact mood, anxiety levels, and overall brain function.
The activation of mast cells can affect sensory nerves, leading to symptoms such as itching, burning, or tingling sensations.
Mast cells can release inflammatory mediators when activated, which can contribute to neuroinflammation. This inflammation can affect the brain and spinal cord, potentially leading to symptoms such as headaches, mood disturbances, and cognitive difficulties.
4. Gut-Health Connection: People with both POTS and MCAS often report gastrointestinal issues. Mast cells are abundant in the gastrointestinal tract and can contribute to symptoms such as nausea or bloating in both MCAS and POTS. Dysregulation in gut function can exacerbate the autonomic dysfunction seen in POTS.
5. Comorbidity: Both conditions are more commonly observed in individuals with EDS (Hypermobile Ehlers-Danlos Syndrome), Fibromyalgia, Chronic Pain, and Rheumatoid arthritis.
The presence of EDS and other chronic pain syndromes might predispose an individual to dysregulation in the autonomic and immune systems, leading to a greater likelihood of developing both POTS and MCAS.
Understanding POTS, MCAS And The Nerve System
In both POTS and MCAS, the autonomic nervous system (ANS) plays a central role.
1. Autonomic Dysregulation: In POTS, there is a problem with how the autonomic nervous system regulates blood flow and heart rate upon standing. Normally, the ANS should adjust blood vessel tone and heart rate to maintain steady blood pressure and blood flow to the brain when a person stands. In POTS, these adjustments are impaired, leading to symptoms.
2. Increased Heart Rate: The primary symptom of POTS is an excessive increase in heart rate when moving to an upright position. This is due to the body’s compensatory mechanism in response to reduced blood flow to the brain, as the ANS tries to maintain blood circulation.
3. Blood Volume and Blood Vessel Tone: People with POTS may have lower blood volume or issues with blood vessel constriction upon standing, which can be related to ANS dysfunction. This contributes to the pooling of blood in the lower extremities, reducing blood return to the heart and brain.
4. Noradrenaline Sensitivity: Some individuals with POTS have heightened sensitivity to adrenaline, a neurotransmitter that affects heart rate and blood vessel constriction. This can exacerbate the increase in heart rate and lead to further ANS imbalance.
5. Neurological Contributions: Certain types of POTS may relate to autoimmune responses or specific physiological changes in neurological function, suggesting that shifts in nervous system regulation play a role in symptom onset and maintenance.
Overactive Sympathetic Nerve System in POTS
The sympathetic nervous system is often referred to as our fight-or-flight division, whereas our Parasympathetic’s is better known as our “Rest and Digest”. The sympathetic nervous system response or overdrive has a significant connection in POTS and MCAS symptoms.
In POTS, when the autonomic nervous system malfunctions, there is often an excessive release of Cortisol, norepinephrine, and epinephrine from the sympathetic nervous system. Studies also point out that there can be insufficient release of acetylcholine from the parasympathetic nervous system. Remember our Nerve system has these two branches almost like a gas pedal and a break. In POTS this imbalance in the nerve system can lead to the symptoms I have been talking about.
In individuals with the hyperadrenergic subtype of POTS, this imbalance and sympathetic overdrive becomes even more pronounced. These extended sympathetic bursts can significantly disrupt both the body and mind, leading to increased blood pressure, damage to blood vessels, restlessness, and a jittery sensation.
Typical POTS Symptoms and the Sympathetic Nervous System
- Tachycardia: Rapid heart rate above 100 beats per minute at rest
- Rapid respiratory rate
- High blood pressure (hypertension)
- Increased pupil diameter (hypersensitivity to light)
- Digestive problems: Rapid gastric emptying or gastroparesis
Many of these symptoms are reported in patients with MCAS as well.
What Causes Or Triggers POTS and MCAS
Postural Orthostatic Tachycardia Syndrome (POTS) and MCAS can be rooted in a variety of underlying factors, We can call these triggers. These triggers might include vaccines, chemicals, viral infection, Gut Health, Hormones, diet, adrenal function, and a combination of other factors that all come together to activate the sympathetic nerve system and the immune system. Let’s take a closer look at these triggers and how POTS and MCAS are connected.
1. Autoimmune Disorders
Autoimmune Diseases: Similarities between POTS and various autoimmune disorders suggest an immune mechanism in a subset of patients. Conditions such as Neuropathy Lupus, Rheumatoid arthritis, Sjogren’s Syndrome, and Celiac disease are linked with POTS. (*) The immune system may attack the autonomic nervous system, leading to a variety of autoimmune diseases.
2. Infections
Viral or Bacterial Infections: Some patients report experiencing POTS symptoms after illnesses such as mononucleosis, Lyme disease, and viral infections. It’s believed that infections may trigger or worsen autonomic dysfunction.
3. Physical Trauma
Injuries and Surgery: Some individuals develop POTS after severe physical trauma, surgery, or concussion. The stress on the body might disrupt the autonomic nervous system.
4. Deconditioning
Lack of Physical Activity: Extended periods of bed rest or a sedentary lifestyle can contribute to POTS by weakening the cardiovascular system and destabilizing blood pressure regulation mechanisms.
5. Hormonal Changes
Hormonal imbalances or changes can exacerbate POTS symptoms. Conditions like thyroid disorders, adrenal gland imbalances, and sex hormone imbalances have been linked to both POTS, MCAS and Histamine Intolerance.
6. Blood Volume and Circulation Issues
Low Blood Volume: Hypovolemia (low blood volume) can be a contributor to POTS. Inefficient circulation and pooling of blood in the lower extremities can lead to symptoms.
Venous Insufficiency: Poor vein function can lead to blood pooling, particularly in the legs, contributing to dizzy and lightheaded feelings upon standing.
7. Nervous System Abnormalities
Dysfunction in Autonomic Nervous System: The sympathetic part of the autonomic nervous system can become overactive, leading to changes in heart rate and blood pressure regulation (*),(*),(*)
8. Histamine Intolerance And Mast Cell Disorders
Mast Cell Activation Syndrome (MCAS): research suggests a link between POTS and disorders involving mast cells, which play a role in allergic reactions and inflammation
9. Stress and Inflammation
Stress can significantly impact both POTS and MCAS patients. Chronic stress activates the Sympathetic Nerve system which leads to an increase in heart rate and blood pressure, which can worsen tachycardia and other POTS symptoms.
The release of stress hormones like cortisol can also heighten mast cell activity, exacerbating MCAS symptoms and promoting inflammation. You can learn more about the effects of stress and high cortisol on Mast cells here.
10. Hyper Adrenergic States
The excessive release of norepinephrine upon standing can contribute to the palpitations, tremors, anxiety, and other symptoms characteristic of hyperadrenergic POTS. Changes in vascular tone result in the pooling of blood in the lower extremities and compensatory heart rate increases to maintain cerebral perfusion.
When the body experiences stress, the adrenal glands release cortisol, which normally helps regulate blood pressure and blood sugar. In hyperadrenergic POTS, this stress response may be overactive, leading to persistently high cortisol levels. High cortisol can exacerbate symptoms like fatigue, exercise intolerance, anxiety, and rapid heart rate commonly seen in POTS patients.
Diagnosis of hyperadrenergic POTS often involves measuring norepinephrine, normetanephrine (urine), levels, and cortisol levels. Treatment typically focuses on managing the elevated sympathetic nervous system activity along with addressing things that fill up the Histamine/MCAS bucket.
Elevated norepinephrine and Cortisol typically seen in hyperadrenergic POTS can have systemic effects that coincide with the systemic inflammatory response driven by histamine in MCAS.
11. COVID Vaccine and Long Haul COVID
POTS and other related conditions have been reported to develop three months post severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but can also develop following vaccination. This suggests that such factors can trigger an autoimmune response in susceptible individuals. The post-COVID-19 cardiovascular autonomic dysfunction can lead not only to a POTS-like pattern but also to blood pressure instability, tachycardia at rest, and local circulatory disorders (*)
Symptomatic Overlap of POTS and MCAS
1. Cardiovascular Symptoms:
POTS leads to increased heart rate and sometimes elevated blood pressure upon standing-central features of POTS. MCAS can cause similar cardiovascular responses due to the release of histamines and other mast cell mediators, potentially contributing to the autonomic dysfunction and hyperadrenergic symptoms seen in POTS. Histamine has a direct inflammatory effect on blood vessels. Both POTS and Histamine intolerance/MCAS share a cardiovascular connection.
2. Neurological Symptoms
Symptoms like anxiety and “brain fog” are seen in both conditions. In hyperadrenergic states, this is often due to excessive norepinephrine, while in MCAS, it may be due to histamine and cytokine release affecting brain function.
3. Gastrointestinal Symptoms:
POTS and MCAS are often connected through a variety of mechanisms in the gut. Both conditions exhibit GI distress like nausea, diarrhea, bloating, or pain, as the autonomic nervous system and mast cell disruptions affect the digestive tract balance and function.
Treatment For MCAS and POTS- A Functional Medicine Approach
The connection between POTS and MCAS is undeniable however managing POTS requires a multidisciplinary approach that addresses identified underlying factors and modulates symptoms. Conventional approaches aim to support blood volume with fluids and electrolytes, manage heart rate, and promote peripheral vasoconstriction with medications. The presentation of dysautonomia is varied, so approaches should be individualized. Individuals diagnosed or experiencing symptoms of MCAS and POTS need to work with not only conventional medical doctors but also a Certified Functional Medicine Practitioner.
POTS patients may benefit from eating several smaller meals, as consuming large meals can redirect blood to the gut for digestion, potentially worsening symptoms. In addition to smaller meals, Dietary Adjustments should include the removal of foods high in histamine. Since certain foods can release histamine or inhibit its breakdown, managing your diet is crucial. You can learn more about a low-histamine diet here as well as download my free E-book on Starting a Low-Histamine Diet here.
Consuming water with salt or electrolytes may be beneficial. Proper hydration can help regulate norepinephrine levels, aiding in the management of blood pressure and symptoms. Patients experiencing hypovolemic symptoms might consider gradually increasing their intake of salt and water, tailored to their individual needs.
Natural electrolyte powders or organic coconut water, which contain potassium, sodium, chloride, and carbohydrates, can also support hydration effectively.
Many individuals with POTS and MCAS experience fewer symptoms when they limit simple carbohydrates and opt for balanced meals that include protein, healthy fats, and complex carbohydrates to stabilize insulin levels. When carbohydrates are consumed, insulin is released to help maintain steady blood sugar levels.
Functional Medicine Testing To Consider When You Have MCAS and POTS
Here are some key lab tests and evaluations that can be beneficial in understanding the POTS and MCAS connection:
Testing for Adrenal Function
Under various stressors such as imbalanced blood sugar, infections, or emotional stress, the adrenal glands produce cortisol. It is crucial to monitor cortisol levels throughout the day to confirm that they are increasing and decreasing in a healthy pattern. This can be effectively evaluated using the Adrenal Function Profile.
The adrenal glands also secrete aldosterone, which plays a vital role in regulating sodium, potassium, and water balance, thereby helping to maintain stable blood pressure. A Comprehensive Neurotransmitter Profile can examine additional connection between both POTS and MCAS when imbalances in norepinephrine, epinephrine, and histamine are suspected.
Testing for Thyroid Dysfunction
If thyroid dysfunction is suspected clinically, a Complete Thyroid Panel can be conducted. This includes measuring thyroid-stimulating hormone (TSH), T3 (both free and total), T4 (both free and total), reverse T3, and antibodies such as anti-thyroglobulin and thyroid peroxidase, using functional medicine ranges for assessment.
Testing for Hydration, Blood Sugar, and Electrolyte Balance
A Comprehensive metabolic profile (CMP) can assess electrolytes, blood glucose, and kidney and liver health.
Testing for Micronutrient Deficiencies
Nutrient deficiencies, including those of B vitamins, magnesium, Vitamin D, and iron, can be evaluated using Micronutrient + test. This test offers a non-invasive evaluation of B vitamins, antioxidants, minerals, digestion, fatty acids, and amino acids.
Testing for Food Allergies
In response to food sensitivities or food allergies, the body may release histamine and cause inflammation, which can prompt the adrenal glands to produce epinephrine and cortisol. This reaction might lead to a functionally hyperadrenergic state, potentially resulting in symptoms of Postural Orthostatic Tachycardia Syndrome (POTS) or your classical histamine intolerance symptoms (Rash, Hives, itchy skin, Gut bloating, headaches, etc) This can be an important test when trying to better understand POTS and MCAS connection.
Testing Gut Health
Many patients find that connection between both POTS and MCAS lies in gut health. A comprehensive stool test can offer an in-depth analysis of gut health, including markers like SIgA and Anti-gliadin SIgA, calprotectin for inflammation, as well as insights into the presence of bacteria, parasites, viruses, yeast, and other indicators of intestinal health.
A Viral load Panel or Tick-Borne Disease Panel can look further for infections associated with nervous system autoimmunity and POTS.
Testing for Mycotoxins and Mold
A Urine Mycotoxin test can offer insight into exposure to these volatile compounds. Mycotoxins are toxic compounds produced by certain types of molds. Exposure to mycotoxins can occur through inhalation of mold spores or ingestion of contaminated food, and it can lead to a range of health problems.
Some individuals with POTS and MCAS report worsened symptoms when exposed to mold or in moldy environments. This is likely due to the impact of mycotoxins on the autonomic nervous system or immune response, which can have diverse effects on the body.
Here’s What You Should Remember About MCAS and It’s Connection To POTS
Understanding the interconnected roles of the sympathetic and parasympathetic nervous systems is vital for managing conditions like POTS and MCAS. Factors such as stress, inflammation, viral load, Gut infections, inflammation, mold, Food allergies, and dietary habits significantly influence these health problems.
By adjusting lifestyle practices, managing diet, and employing appropriate stress-reduction techniques, individuals can find relief and improve their quality of life despite these challenging conditions. For more comprehensive insights on managing chronic conditions and maintaining optimal health, explore my blog and stay informed with expert advice and practical tips.
