December 22, 2021 9:00 pm


Despite its crucial role, the nervous system’s role in histamine intolerance often goes unnoticed.

The nervous system controls essential body functions to restore health. 

It sends signals throughout the body to maintain homeostasis and restore health. One of those signals is histamine.  

This link explains why symptoms appear diversely throughout the body.

In this blog post, I explore the fascinating interplay between the nervous system and histamine, revealing how this molecule unexpectedly impacts your health.

The Nervous System: A Hidden Source of Histamine

Histamine is crucial in the body’s response to danger.

It regulates various body functions. Specifically, when physical stress occurs—such as dehydration, prolonged fasting, blood loss, or severe infection, the nervous system instructs the body to release histamine.

Similarly, during emotional stress, it instructs the body to release histamine, which alters hormones and other neurotransmitters as part of the stress response.

Ideally, this histamine system is tightly regulated. That is, it produces histamine and degrades any excess.

However, the histamine system can also become dysregulated. 

Specifically, histamine intolerance symptoms occur when stressors exceed the nervous system’s capacity to address them. Similarly, they will resolve with the resolution of stressors.

Therefore, understanding this complex interaction is essential to restoring health.

How The Nervous System and Histamine Affects Brain Function

Histamine produced in the body does not pass the blood-brain barrier. 

Instead, the brain synthesises histamines from histidine in the bloodstream and deactivates any excess through methylation. Afterwards, histamine is stored inside the brain and released upon stimulation.

Furthermore, histamine acts as a neurotransmitter in the brain, sending signals throughout the nervous system. This system then delivers histamine to specific areas, determining the symptoms experienced.

Importantly, research in 2024 identified that diamine oxidase, traditionally known for regulating histamine in the gut, also affects the brain. This research suggests a complex interplay.

Histamine receptors, H1, H2, H3, H4, Histamine Intolerance, Nervous system, Alison Vickery, Health,. Australia

Understanding Histamine's Key Players: The Four Receptors

Four receptors for histamine are known: H1R, H2R, H3R, and H4R. The first three are widely present in the brain, while H4R is not.

Firstly, H1R excites neurons in the brain and is mainly responsible for arousal and awakening. This explains why H1R antihistamines that cross the blood-brain barrier (though not all do) sedate the brain.

Additionally, H2R excites neurons and is primarily responsible for perception, learning, pain, reward, and neuroplasticity. This is why H2R histamines crossing the blood-brain barrier can affect a person’s pain perception.

In contrast, H3R is inhibitory and controls the release of neurotransmitters, including histamine, from brain neurons. Consequently, H3R drugs and methylation are promising targets for addressing histamine dysregulation in the brain.

Moreover, H4R is excitatory and controls the release of neutrophils from the bone marrow and white blood cells. It is not found within the brain but communicates with it via the nervous system.

Therefore, these histamine receptors, H1, H2, and H3, play vital roles in assessing danger. They communicate via the nervous system, involving the H4 receptor and the immune system. In turn, explaining the wide-ranging role of histamine in the body. 

Histamine, Nervous system

How Histamine Impacts The Body

Wide-ranging symptoms characterize histamine intolerance due to the effects of histamine signaling throughout the body via the nervous system. Common histamine symptoms include:

The Nervous System


Firstly, the nervous system and histamine causes anxiety and signals danger. People with histamine intolerance often feel “free-floating anxiety.”


Furthermore, the nervous system and histamines regulate sleep, causing insomnia or hypersomnia. Histamine levels vary with the sleep-wake cycle, making insomnia a dominant symptom.


Additionally, histamine also affects noradrenaline and serotonin release in the brain, potentially leading to depression. Many antidepressants block histamine receptors. Recent research shows that people with major depressive disorder have low diamine oxidase levels.

Addictions and Compulsive Behaviours

Moreover, histamine further influences addiction and compulsive behaviors. Addictive substances interfere with histamine activity, and withdrawal can cause severe symptoms.

Pain Perception

Lastly, histamine mediates itching and pain. It promotes pain relief through H2R and increases pain through H1R. Blocking H3R can have analgesic effects.

The Immune System and Nervous System Connection

Allergic Reactions

Then, histamine plays a crucial role in the body’s immune response. It is released by mast cells and basophils by the nervous system during allergic reactions and helps to mediate inflammation and other immune responses.

Diamine Oxidase, Histamine Intolerance,Nervous System, Minerals, Vitamins, Alison Vickery, Health, Australia

The Gastrointestinal System and Nervous System Connection

Stomach Acid Regulation

Next, histamine regulates stomach acid production by binding to H2 receptors in the stomach lining. This action is crucial for digestion, helping break down food and kill harmful bacteria. Taking H2 antihistamines blocks the production of stomach acid, exposing us to infections.

Gastrointestinal Motility

Additionally, the nervous system and histamine influence gastrointestinal motility. It stimulates smooth muscle contraction in the intestines, affecting foods’ movement through the digestive tract.

The Respiratory System and Nervous System Connection

Airway Constriction

Next, the nervous system and histamine can cause airway constriction, which is the narrowing of the airways in the lungs. This action is significant in conditions like asthma and allergic reactions.

The Vestibular System and Nervous System Connection

Motion Sickness

Then, histamine plays a role in motion sickness and vomiting. Anti-histamines effectively treat these symptoms.

The Cardiovascular System and Nervous System Connection

Blood Pressure

Next, histamine can raise blood pressure by tightening blood vessels, which increases resistance and leads to higher pressure.


Additionally, histamine can cause tachycardia, a fast heartbeat, by triggering the heart to beat quicker than usual.

histamine intolerance, mast cell activation, medicines, cell danger response, antidepressants, brain fog, nervous system EMF Health Effects

The Endocrine System and Nervous System Connection

Adrenal Fatigue

Then, histamine regulates the adrenal glands and hormone release under stress, often leading to adrenal fatigue with histamine intolerance.

Estrogen Dominance

Furthermore, histamine and estrogen promote each other’s release, worsening histamine intolerance before menstruation and during peri-menopause.

Thyroid Issues

Additionally, the nervous system and histamine controls thyroid hormone release, affecting energy metabolism and causing thyroid issues.

Metabolic Syndrome

Moreover, the nervous system and histamine regulates leptin, which affects appetite. As a result, histamine levels can influence obesity, insulin resistance, and high cholesterol.

Appetite Control

Lastly, brain histamine regulates appetite. H3R antagonists suppress food intake, while H1R antagonists stimulate appetite, affecting weight management.

By recognising these diverse symptoms and their link to the nervous system, you can better manage histamine intolerance and improve your overall health and well-being.

infections, histamine intolerance, mast cell activation, diamine oxidase, autoimmunity, Alison Vickery, Health, Australia


In conclusion, understanding the profound relationship between the nervous system and histamine is vital to restoring health.

Recognising the intricate dance between histamine and the autonomic nervous system can help you better manage symptoms and restore your health.

As you navigate your health journey, remember histamine’s vital role and explore ways to maintain balance within your body.

Ultimately, your well-being is worth it.

You can learn more about managing histamine intolerance on these blog posts.

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