Medicines & Supplements A to Z > Vitamin B2 (Supplement)

Vitamin B2 (Supplement)

Last updated on 18/03/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Riboflavin / Vitamin B2


BRAND NAME(S) IN HONG KONG: Actionvit, B Complex 50, Centrum Junior, Nature’s Way

DRUG CLASS: Vitamin (water soluble) 

USED FOR: Dietary supplementation for Vitamin B2 deficiency 

OTHER DRUGS IN THE SAME CLASS: Vitamin B complex, Vitamin C, Folic Acid

– 50mg, 100mg (tablets)

What is Vitamin B2 for?

Vitamin B2 is a vitamin that is important for converting the food you eat into energy. It also regulates cellular functions and drug metabolism in your body. The recommended daily dietary intake of Vitamin B2 for adults is 1.3 mg (men) and 1.1 mg (non-pregnant women). You should only take a Vitamin B2 supplement when you have a Vitamin B2 deficiency or are unable to take sufficient Vitamin B2 from your diet. Vitamin B2 deficiency is rare, but can cause hair loss, cracked lips, mouth sores, sore throat and itchy eyes. If you are a vegetarian, a person who consumes little milk, or if you are pregnant, you may be at higher risk of Vitamin B2 deficiency.

How to use it?

Vitamin B2 is usually taken as part of a multivitamin or can be taken on its own as a supplement. The usual adult dose is one tablet (10-100 mg) once.

What are the side effects of Vitamin B2?

The side effect of taking Vitamin B2 supplement is that your urine might become yellow and orange in colour.

Who should not take Vitamin B2?

No specific situation or population in which Vitamin B2 should not be used are reported.

Pharmacist Tips:

It is always highly recommended to get nutrients like Vitamin B2  from natural sources first. Food rich in Vitamin B2 are organ meats, dairy products, green vegetables, eggs, whole grain cereals and mushrooms. 

Common dosing schedule:
Take Vitamin B with food. 

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Vitamin B2 may interact with:
Vitamin B2 does not have known significant drug interactions. 

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Vitamin B2 in Hong Kong?

In Hong Kong, Vitamin B2 can be purchased without a prescription from any retail outlet in Hong Kong. This includes grocery stores, convenience stores, medicine shops, and pharmacies. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health. 

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Vitamin B2 in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.