Anorexia of somatic or psychogenic origin in underweight patients, in whom prevention of vitamin-b deficiency secondary to impaired dietary intake or absorption (e.g. as a consequence of antibiotics or other drug therapy interfering with absorption or utilization of b-group vitamins) is indicated. priority should always be given to identifying and treating the underlying cause of anorexia, such as infectious or parasitic diseases, chronic diarrhea, anorexia nervosa or depressive states in the elderly.