Dr. Jess likes this product for those with mast cell activation syndrome and histamine intolerance, especially with those who have migraine headaches with their histamine response as Histo-X contains butterbar! Histo-X™ is a unique way to approach histamine-related pathways.* This advanced formula supports the body’s healthy response to foods and other environmental factors.* Histo-X may support the immune system together with certain physiological systems, such as the cardiovascular, respiratory, and gastrointestinal systems.*