HistDAO^™ is an enzyme formula containing diamine oxidase (DAO)—the main enzyme responsible for the degradation of ingested histamine. This enzyme has been clinically tested and found to break down food-derived histamine in the digestive tract. DAO is not absorbed and does not have systemic activity. HistDAO does not manage or address antibody-related or IgE-related food allergies.*

Ingredients:

Pig Kidney Extract (providing 20,000 HDU diamine oxidase (DAO))