The brain and body naturally produce histamine, a chemical compound that is critical for immune responses, digestion, wakefulness, and cognition. Histamine is also found in a wide variety of healthy and not so healthy foods. If a person’s ability to break down histamine is impaired, excess histamine can build up as the day goes on, causing the “histamine bucket” to overflow.

This can be especially problematic at night because excess histamine can cause a variety of uncomfortable symptoms that interfere with sleep. Excess histamine causes hyperarousal and can trigger symptoms that feel like a panic attack. Symptoms can become more pronounced a few hours after dinner and peak in the middle of the night. Common symptoms include a racing or pounding heart, hot flashes, and feeling too alert and anxious at night. This might come along with physical symptoms such as acid reflux, gas, bloating, itchy skin, hives, headaches, and nasal congestion. Usually, a person will only have one or two of these symptoms.  The symptoms may come and go, or occur regularly but flares up on some nights.

A person might fall asleep fine, only to wake an hour or two later with symptoms. The person might notice that they felt fine all day, and only feel anxious at night. Or they might blame these symptoms on stress. They may indeed experience more histamine intolerance during times of stress because epinephrine released in response to stress can cause the body to release more of its own histamine, causing the histamine bucket to overflow more easily. It can be difficult to identify histamine intolerance as a problem because these symptoms overlap with so many other common medical problems.

A person can be genetically susceptible to histamine intolerance and develop it over time for a variety of reasons. One common reason is chronic low grade gut inflammation that impairs the gut’s production of an enzyme called DAO. DAO normally breaks down dietary histamine in the gut and limits its absorption into the body.

Histamine intolerance can be diagnosed when symptoms improve after going on a low histamine diet. Over time, histamine containing foods are gradually reintroduced to a degree that is tolerated. Supplements containing DAO enzymes taken with meals can be helpful along with other nutrients that support cellular pathways that break down histamine.

Medical Disclaimer: The information mentioned in this article is not intended to diagnose, treat, cure, or prevent any disease. The information provided is for educational purposes only and is not intended to replace the relationships with your medical provider(s). Before initiating any treatment, please first consult with your licensed medical provider.