Vitamin B2, also known as riboflavin, can be taken even while breastfeeding. Although it can be excreted within the breast milk, it is only a vitamin and is not harmful to the baby. If there is an indication for the use of vitamin B2 during breastfeeding, it can be used under medical supervision. The use of vitamin B2, which promotes the repair of epithelial cells, is mostly used in the treatment of mouth ulcers. After taking this medication, there is often a yellowish color of urine, which is normal and belongs to drug staining.