Vit A: Dermatitis, photosensitivity reactions. Vit B
2: Yellow-orange urine discoloration. Fe (>60 mg): Epigastric pain/discomfort, nausea, diarrhea or constipation; fecal impaction (in elderly); anorexia, black/dark stools, bloating, GI irritation, heartburn, metallic taste vomiting; exacerbation of diarrhea in patients w/ inflammatory bowel disease; hemosiderosis (in long-term use of large amounts). Brewer's yeast: Stomach discomfort, flatulence, migraine, headaches.