Vitex agnus-castus is a herb native to the Mediterranean countries and its popularity has increased significantly in recent years, with over 300 publications in the international literature on its mechanism of action. The Vitex berries used in the preparation of the extract contain a wide range of phytochemically active substances, including flavonoids and a group of chemicals called iridoids, including aucubin and agnuside. Vitex can be used together with other dietary supplements such as Vitamin B6 and Evening Primrose Oil.