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Generic name: riboflavin systemic

Brand names: Vitamin B2, B2-400

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Capsule, Oral:

B-2-400: 400 mg

Generic: 50 mg

Tablet, Oral:

Generic: 25 mg, 50 mg, 100 mg


Mechanism of Action

Component of flavoprotein enzymes that work together, which are necessary for normal tissue respiration; also needed for activation of pyridoxine and conversion of tryptophan to niacin



Readily via GI tract; increased with food




9% eliminated unchanged in urine

Half-Life Elimination

Biologic: 66 to 84 minutes

Use: Labeled Indications

Dietary supplement

Use: Off Label

Prevention of migraine headachebyes

Data from randomized, placebo- and active-controlled trials supports the use of riboflavin as a preventative treatment to decrease the frequency, duration, and severity of migraine headaches Rahimdel 2015, Shoenen 1998. Additional trials may be necessary to further define the role of riboflavin in this condition.

Based on the American Headache Society and American Academy of Neurology guidelines for migraine prevention, riboflavin is probably effective for migraine prevention AHS/AAN [Holland 2012]. Similarly, guidelines from the Canadian Headache Society give riboflavin a strong recommendation based on low-quality evidence for use as a preventative treatment for migraines CHS [Pringsheim 2012].

Dosage and Administration

Dosing: Adult

Dietary supplement: Oral: 100 mg once or twice daily

Prevention of migraine headache (off-label use): Oral: 400 mg once daily (Rahimdel 2015; Schoenen 1998)

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Dietary supplement: Infants, Children, and Adolescents: A multivitamin preparation is most commonly used for the provision of riboflavin supplementation in pediatric patients; the use of a single-ingredient riboflavin product as a daily supplement for the prevention of deficiency in pediatric patients is very rare. If single-ingredient riboflavin supplement is necessary, consult product labeling for appropriateness of product in infants and young children in particular.

Migraine headache, prevention: Limited data available, efficacy results variable: Children ≥ 8 years and Adolescents: Oral: 200 to 400 mg once daily; dosing based on a retrospective study of 41 patients (ages 8 to 18 years) who received 200 mg/day (n=21) or 400 mg/day (n=20) as prophylaxis for migraine and migraine-type headaches; results showed significant reduction in primary endpoint of frequency of headache attack; 68.4% of patients had a ≥50% decrease in headache frequency during treatment (Condò 2009). However, in a prospective, placebo-controlled study of 48 patients (ages 5 to 15 years), patients received 200 mg/day (n=27) or placebo (n=21) and in the treatment group (riboflavin) no benefit compared to placebo for migraine frequency or intensity was observed; a high placebo responder rate was also reported (MacLennan 2008).

Dietary Considerations

Dietary sources of riboflavin include liver, kidney, dairy products, green vegetables, eggs, whole grain cereals, yeast, and mushroom.

Dietary reference intake (IOM 1998):

1 to 6 months: Adequate intake: 0.3 mg/day

7 to 12 months: Adequate intake: 0.4 mg/day

1 to 3 years: RDA: 0.5 mg

4 to 8 years: RDA: 0.6 mg

9 to 13 years: RDA: 0.9 mg

14 to 18 years: RDA: Females: 1 mg; Males: 1.3 mg

≥19 years: RDA: Females: 1.1 mg; Males: 1.3 mg

Pregnancy: RDA: 1.4 mg

Lactation: RDA: 1.6 mg


Protect from light.

Drug Interactions

There are no known significant interactions.

Test Interactions

Large doses may interfere with urinalysis based on spectrometry; may cause false elevations in fluorometric determinations of catecholamines and urobilinogen

Adverse Reactions

Frequency not defined: Genitourinary: Urine discoloration (yellow-orange)


Other warnings/precautions:

  • Vitamin deficiency: Single vitamin deficiency is rare; evaluate for other deficiencies.


Pregnancy Considerations

Water-soluble vitamins cross the placenta. Riboflavin requirements may be increased in pregnant women compared to nonpregnant women (IOM 1998).

Patient Education

  • Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
  • Patient may experience urine discoloration (HCAHPS).
  • Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Source: Wolters Kluwer Health. Last updated September 5, 2019.