Vitamin B2 Toxicity

Also known as riboflavin, vitamin B2 is essential to your body’s metabolism of fats, amino acids and carbohydrates. Vitamin B2 also works to make folic acid and vitamin B6 usable in your body. Although vitamin B2 rarely causes toxicity, the daily requirement of this water-soluble vitamin is rather small. Before you begin taking a vitamin B2 supplement, consult your doctor.


Vitamin B2 assists your body with metabolizing carbohydrates into energy by creating adenosine triphosphate – ATP. You also need vitamin B2 to utilize other B-complex vitamins. Vitamin B2 also appears to have antioxidant actions in the body, destroying free radicals that harm your body’s cells and cell DNA, according to the University of Maryland Medical Center 1. Additionally, riboflavin plays an important role in red blood cell creation and healthy growth.


You can get vitamin B2 from your diet by eating eggs, dairy, meat, whole grains and leafy green vegetables, notes the University of Michigan Health System. People who don’t get enough vitamin B2 may need to take a supplement, usually in the form of a B-complex vitamin. The daily recommended requirement of vitamin B2 is 1.1 mg for women and 1.3 mg for men, but pregnant women may need more – about 1.4 milligrams, notes the University of Pittsburgh Medical Center 1. Breastfeeding women need 1.6 mg of riboflavin per day, while infants need 0.3 to 0.4 mg. Children 1 to 8 years old need 0.5 to 0.6 mg, and adolescents 9 to 13 years old require 0.9 mg of vitamin B2 daily. Teenaged boys 14 years of age and older have the adult requirement of riboflavin, while girls aged 14 to 18 years old need 1 mg.

The therapeutic doses of vitamin B2 and those found in multivitamins are much higher. Multivitamin supplements often contain 20 to 25 mg of vitamin B2, and therapeutic doses can reach up to 400 mg per day.


Although the amounts of vitamin B2 found in multivitamin supplements and in your diet don’t pose any risks of toxicity, the therapeutic dosages could provide excessive amounts of riboflavin, according to the University of Pittsburgh Medical Center 1. Despite the large amounts, vitamin B2 appears to be very safe, however. Even at extremely high doses, vitamin B2 rarely causes side effects, much less toxicity, notes the University of Maryland Medical Center 1. Reported side effects from taking more than 10 mg per day of riboflavin include sun-induced eye damage, itching or numbing sensations, and orange-tinted urine.


Certain therapeutic uses have arisen for vitamin B2 supplements. For example, you might take riboflavin supplements if you have migraines, cataracts, anemia, night blindness or canker sores, notes the University of Michigan Health System. Vitamin B2 may also help in treating Parkinson’s disease, sickle cell anemia and preeclampsia. People who want to enhance their sports performance and those with HIV/AIDS could benefit from taking a riboflavin supplement as well, notes the University of Pittsburgh Medical Center 1. No conclusive medical research supports the use of vitamin B2 supplements for treating or preventing any health condition other than a specific deficiency, however.


Vitamin B2 supplements could interact negatively with certain other medications and supplements. Talk with your physician before taking extra riboflavin if you’re also taking the antibiotic tetracycline, tricyclic antidepressants, the gout drug probenecid, Dilantin for epilepsy or the cancer drug doxorubicin, warns the University of Maryland Medical Center 1. Also, keep in mind that taking large amounts of one B-complex vitamin can cause an imbalance of other B-vitamins. That’s why you should consider taking vitamin B2 in a supplement that contains other B-complex vitamins, especially vitamins B1, B3 and B6, advises the University of Michigan Health System.