Histamine Blend SP-33 is formulated to help support a healthy histamine response. This powerful formula includes a proprietary blend of Montmorillonite Clay, Horehound, Mullein, Wild Cherry, Barberry, and Peppermint. Believed to work better together in a blend, these powerful herbs contain flavonoids, alkaloids, sterols, tannins, and more may help support a healthy, normal histamine response and respiration. Like all Solaray products, Histamine Blend SP-33 is lab verified for purity, potency and identity. p>