Histamine intolerance affects us in different ways, because histamine is found all throughout the body. Histamine always causes inflammation, but the symptoms that present themselves vary based on which receptors are being activated, and where.
In the heart, histamine functions as a vasodilator, meaning that it widens our blood vessels, and therefore there is less resistance to blood pumping through the body. Imagine a running hose that is widened, suddenly allowing more water to flow through, with less resistance or pressure. Just like this hose, the widening of blood vessels and decrease in resistance causes a drop in blood pressure. At the same time, your heart rate increases, as it works to get the same volume of blood through the widened vessels.
The combination of rapid heart rate and change in blood pressure can cause feelings of high anxiety, especially when they bring with them a pounding heart, shortness of breath, “flushing”, a rise in body temperature, dizziness, and/or redness in the face. Some people might feel that they are having a panic attack, when in reality the problem is excess histamine.
Excess histamine might help to explain panic attack symptoms that don’t appear to be linked to a panic disorder.
Beyond the heart, inflammation in the brain caused by excess histamine has also been linked to anxiety (as well as a series of other psychiatric presentations that are in fact, again, symptoms of histamine intolerance).
While the causes of histamine intolerance vary (and therefore so does the solution), a low-histamine diet is often a great place to start.