B-Plex is a specialised formulation of B vitamins which excludes vitamin B12 and folic acid. It may be that certain metabolic types such as high histamine formers tolerate this formulation more readily. B vitamins are needed for the release of energy from food, for the healthy function of the nervous system and for the correct balance of hormones. B vitamins are essential for good circulation, a strong immune system and for healthy skin, hair and eyes.