Riboflavin, also known as vitamin B₂, enables carbohydrates, proteins, and fats to release energy. Riboflavin is needed for normal reproduction, growth, and repair of skin, hair, nails, and joints. It is also important to the immune system, which protects your body against disease.

Here is a partial list of the illnesses that riboflavin helps prevent, and those that it helps to treat:

• Migraine headache. Riboflavin may help prevent migraine headaches. Studies have suggested that supplementation with riboflavin is more effective than aspirin in preventing these severe headaches.
• Cataracts. Riboflavin deficiency may cause cataracts. Riboflavin is vital to the activity of an enzyme that protects your eyes. Riboflavin deficiency is fairly common in older people. Before taking more than the recommended dietary allowance (RDA) for riboflavin to prevent cataracts, speak to your health care provider.
• Riboflavin supplements may help in the treatment of sickle cell anemia. It may also enhance the effectiveness of iron supplements in the treatment of anemia.
• Rheumatoid arthritis. Too little riboflavin in your diet may put you at risk for rheumatoid arthritis. Supplementation with riboflavin may help improve your symptoms.

Riboflavin is also helpful in the following ways:

• May relieve symptoms of carpal tunnel syndrome
• Reduces the effects of stress
• Skin problems such as acne (especially acne rosacea), dermatitis, eczema, and ulcers may improve with riboflavin supplementation
• May improve muscle cramps
• May protect against certain types of cell damage that occur during a heart attack or stroke
• Enhances immune function

The best sources of riboflavin include brewer's yeast, almonds, organ meats, whole grains, wheat germ, wild rice, mushrooms, soybeans, milk, and spinach.

Riboflavin is added to flours and cereals. Riboflavin is destroyed by light and alkalis such as baking soda. It is not destroyed by heat, although it will leach into cooking water. Foods should be stored away from light to help retain their riboflavin content.

Riboflavin supplements are available in two forms: simple or activated. It is also found in multivitamin preparations and in B-complex vitamins, in 25-, 50-, and 100-mg tablets.

As with all medicines, check with a healthcare provider before giving riboflavin supplements to a child.

Daily recommendations for dietary riboflavin are listed below.

Pediatric

• Infants birth to 6 months: 0.3 mg (adequate intake)
• Infants 7 to 12 months: 0.4 mg (adequate intake)
• Children 1 to 3 years: 0.5 mg (RDA)
• Children 4 to 8 years: 0.6 mg (RDA)
• Children 9 to 13 years: 0.9 mg (RDA)
• Males 14 to 18 years: 1.3 mg (RDA)
• Females 14 to 18 years: 1 mg (RDA)

Adult

• Males 19 years and older: 1.3 mg (RDA)
• Females 19 years and older: 1.1 mg (RDA)
• Pregnant females: 1.4 mg (RDA)
• Breastfeeding females: 1.6 mg (RDA)

Riboflavin toxicity is rare. Possible reactions to high doses include itching, numbness, burning or prickling sensations, and sensitivity to light. High doses of riboflavin can affect urinalysis test results.

Poor dietary habits in combination with birth control medications can interfere with the body's ability to use riboflavin.

Riboflavin can reduce the effectiveness of sulfa-containing medications (antibiotics used to treat bacterial infections).

Riboflavin may reduce the effectiveness of medications taken for malaria (such as chloroquine, mesloquine).

Riboflavin interacts with selegiline, a medication used for Parkinson's disease.

Riboflavin may interact with doxorubicin, a medication used for the treatment of certain cancers.

Methotrexate, a medication used to treat cancer, can prevent the body from making riboflavin (as well as other essential vitamins).

Phenytoin, a medication used to control epileptic seizures, may affect riboflavin levels in children.

Psychotherapeutic medications called phenothiazines (such as chlorpromazine) may lower riboflavin levels. Tricyclic antidepressants (imipramine, amitriptyline) also reduce levels of riboflavin in the body. Please refer to the depletions monographs for these medications for more information.

Taking riboflavin may improve treatment with antidepressants such as nortriptyline, especially in elderly patients. However, you should check with your healthcare provider before adding new supplements to your existing medication regimen.

Riboflavin should not be taken at the same time as tetracycline, an antibiotic, because it interferes with the absorption and effectiveness of this medication. Vitamin B complex supplements should be taken at different times from tetracycline.

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