Natural Factors Pantothenic Acid B5 - 250 mg - Known as the "anti-stress vitamin", Vitamin B5 (d-Pantothenic Acid) plays a major role in the production of adrenal hormones and the formation of antibodies, as well as aiding in the conversion of fats, carbohydrates and proteins into energy. Thought to be helpful in treating stress and anxiety, deficiency of Vitamin B5 may cause fatigue, headaches, nausea and tingling in the hands.