Hi Friend,
If you've been managing ADHD symptoms alongside your chronic illness journey, you're not alone—and the connection may be deeper than you think. Emerging research is revealing a fascinating link between Mast Cell Activation Syndrome (MCAS) and ADHD that could explain why so many people in our community experience both conditions.
What is MCAS?
Mast Cell Activation Syndrome occurs when mast cells—your immune system's first responders—become overly reactive and release excessive amounts of chemical mediators like histamine, tryptase, and prostaglandins. These mediators can affect virtually every system in your body, creating a cascade of seemingly unrelated symptoms.
Common MCAS symptoms include:
Skin reactions (flushing, hives, itching)
Digestive issues (bloating, nausea, IBS-like symptoms)
Cardiovascular symptoms (rapid heart rate, blood pressure changes)
Respiratory problems (shortness of breath, nasal congestion)
Neurological symptoms (brain fog, headaches, anxiety)
Fatigue and difficulty concentrating
The ADHD Connection: More Than Coincidence
Research suggests that individuals with MCAS have significantly higher rates of ADHD and attention difficulties than the general population. But why?
The Histamine-Brain Pathway
Histamine isn't just an allergy chemical—it's also a crucial neurotransmitter in the brain. When mast cells release excessive histamine, it can significantly impact cognitive function, attention, and executive functioning. High histamine levels can cause:
Difficulty maintaining focus and concentration
Mental restlessness and racing thoughts
Impulsivity and emotional dysregulation
Sleep disturbances that worsen ADHD symptoms
Brain fog that mimics or exacerbates ADHD
The Inflammation Factor
MCAS creates chronic inflammation throughout the body, including in the brain. Neuroinflammation has been increasingly linked to ADHD symptoms, affecting dopamine pathways and neurotransmitter balance. For many people with both conditions, treating the underlying mast cell dysfunction can significantly improve their ADHD symptoms.
Why This Matters for Our Community
If you have fibromyalgia, hEDS, or other chronic conditions common in our community, you're already at higher risk for both MCAS and ADHD. Understanding this connection means:
Your ADHD symptoms might improve with MCAS treatment
Your 'brain fog' might have a treatable physical cause
You might be able to reduce both sets of symptoms with targeted interventions
You deserve a comprehensive approach that addresses all your symptoms
Treatment Possibilities
Managing MCAS can involve several approaches that may also help with ADHD symptoms:
Antihistamines (H1 and H2 blockers) to reduce histamine effects
Mast cell stabilisers to prevent excessive mediator release
Low-histamine dietary modifications
Identifying and avoiding personal triggers
Supporting overall immune system regulation
When MCAS is properly managed, many people report clearer thinking, better focus, improved emotional regulation, and reduced need for ADHD medications—or better responses to them.
Could You Have MCAS?
Consider MCAS if you experience:
Multiple unexplained symptoms affecting different body systems
Symptoms that flare with certain foods, stress, or environmental triggers
ADHD symptoms that seem to worsen with allergic or inflammatory reactions
Chronic issues that haven't responded well to conventional treatments
A diagnosis of fibromyalgia, hEDS, POTS, or autoimmune conditions
Understanding the MCAS-ADHD connection could be the missing piece in your health puzzle. A comprehensive consultation can help determine whether mast cell dysfunction is contributing to your symptoms and guide you toward more effective treatment strategies.
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Remember: Your symptoms are real, they're connected, and there are pathways to improvement.
Stay Well
General Disclaimer: The information contained in this newsletter is provided by MEND Clinic for educational and informational purposes only. It is not intended as, and should not be used as a substitute for, professional medical advice, diagnosis, or treatment. Accessing this content does not establish a doctor-patient relationship. Because the conditions we discuss (including hEDS, MCAS, and POTS) are complex and highly individual, what works for one person may be contraindicated for another. Always seek the advice of your own physician or qualified healthcare provider before making any changes to your medication, supplements, or lifestyle. Reliance on any information provided in this newsletter is solely at your own risk.
