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Generic Name: riboflavin (vitamin B2) (RYE bow flay vin)
Brand Name: B2-400, Vitamin B2

What is B2-400 (riboflavin)?

Riboflavin is vitamin B2. Vitamins are naturally occurring substances necessary for many processes in the body. Riboflavin is important in the maintenance of many tissues of the body.

Riboflavin is used to treat or prevent deficiencies of riboflavin.

Riboflavin may also be used for purposes not listed in this medication guide.

What is the most important information I should know about B2-400 (riboflavin)?

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

What should I discuss with my healthcare provider before taking B2-400 (riboflavin)?

Ask a doctor or pharmacist if it is safe for you to use this medicine if you have other medical conditions, especially:

  • gallbladder disease; or

  • cirrhosis or other liver disease.

Riboflavin is considered likely safe to use during pregnancy, but your dose needs may be different during this time. You should not use riboflavin without a doctor's advice if you are pregnant.

Riboflavin is considered possibly safe to use while nursing, and your dose needs may be different during this time. Do not use riboflavin without a doctor's advice if you are breast-feeding.

Do not give riboflavin to a child without medical advice.

How should I take B2-400 (riboflavin)?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

The recommended dietary allowance of riboflavin increases with age. Follow your healthcare provider's instructions. You may also consult the Office of Dietary Supplements of the National Institutes of Health, or the U.S. Department of Agriculture (USDA) Nutrient Database (formerly "Recommended Daily Allowances") listings for more information.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking B2-400 (riboflavin)?

Follow your healthcare provider's instructions about any restrictions on food, beverages, or activity.

B2-400 (riboflavin) side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor if you have diarrhea or increased urination. These could be signs that you are using too much riboflavin.

Riboflavin may cause your urine to turn a yellow-orange color, but this is usually not a harmful side effect.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect B2-400 (riboflavin)?

Other drugs may interact with riboflavin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about riboflavin.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 3.02.

Date modified: October 14, 2016
Last reviewed: August 10, 2016