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Folic Acid

Folic Acid, also known as Vitamin B9, folate or folacin, is a water-soluble vitamin that is crucial for proper cell growth and DNA formation.

Last Modified: 16 May 2024

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What is Folic Acid? 

Folic Acid, also known as Vitamin B9, folate or folacin, is a water-soluble vitamin that is crucial for proper cell growth and DNA formation.   

Folic Acid is commercially synthesized through chemical processes to be bioavailable as a vitamin supplement or food fortificant. 

Global Name

Generic name:  Folic Acid, folate, vitamin B9 or folacin (old name)  
Brand names: Folvite, Folicet, Folicil


What is Folic Acid used for? 

Folic Acid is used to prevent and treat low blood levels of folate (folate deficiency), as well as its complications, including anemia and the inability of the bowel to absorb nutrients properly. It is also used by women of childbearing age and pregnant women to prevent neural tube defects in the developing fetus especially in the first trimester. 

How do you use Folic Acid? 


Folic Acid is available in tablet form, liquid solution, and as an injectable.

Dosage information: 

  • Adults: 400 to 800 mcg daily 
  • Pregnant women: 600 mcg daily 
  • Breastfeeding women: 500 mcg daily 
  • Children: Dosage varies based on age and dietary needs 


  • Children: Suitable with proper dosage. 
  • Adults: Suitable for adults. 
  • Elderlies: Suitable for elderly individuals.

Is there anyone who can’t take Folic Acid? 

  • Individuals who are allergic to Folic Acid or any of its components should not take this supplement. 
  • Patient with low vitamin B12 levels 

Any warnings and precautions : 

  • Folic Acid should not be used to treat anemia without a doctor's advice if the cause of the anemia is unknown. 
  • High doses can mask symptoms of vitamin B12 deficiency. 

Folic Acid should be used cautiously with medications that affect its metabolism, such as methotrexate, and with antiepileptic drugs.  

Side Effects

Side effects are rare but may include allergic reactions like rash, itching/swelling, dizziness, and trouble breathing if an allergy exists.

Pharmacist Tips

  • Comprehensive Health Check: Before starting a Folic Acid supplement, it's advisable to get a complete blood count (CBC) and vitamin B12 levels checked. This helps to identify any underlying issues that could be masked by taking Folic Acid, such as vitamin B12 deficiency anemia. 
  • Correct Dosage: Stick to the recommended dosage unless directed otherwise by a healthcare provider. Overconsumption of Folic Acid, especially in doses over 1,000 mcg (1 mg) daily, can potentially cause adverse effects and mask symptoms of other conditions. 
  • Interaction with Medications: If you are on medications that affect folate metabolism, such as methotrexate for rheumatoid arthritis or certain cancer drugs, consult with your pharmacist or doctor about the proper use of Folic Acid to avoid interactions. 
  • Alcohol Consumption: Limit alcohol intake, as alcohol can interfere with the metabolism of Folic Acid and increase the risk of folate deficiency. 
  • Prenatal Health: Women planning to conceive or who are in the early stages of pregnancy should start taking Folic Acid before conception and continue through the first 12 weeks of pregnancy to help reduce the risk of neural tube defects. 
  • Dietary Sources: While taking a supplement, don't forget that you can also get Folic Acid from your diet. Good sources include dark leafy greens, citrus fruits, beans, peas, lentils, and fortified foods like cereals and bread. 
  • Regular Monitoring: For those taking Folic Acid for specific medical conditions, regular monitoring of folate levels may be necessary to ensure the supplement is having the desired effect. 
  • Sunlight Exposure: Folic Acid can be broken down by UV light, so it's important not to store the supplements in direct sunlight. 
  • Missed Dose: If you miss a dose of your Folic Acid supplement, take it as soon as you remember. If it's almost time for your next dose, skip the missed dose—do not double up to make up for the missed one. 
  • Nutritional Deficiencies: If you have a malabsorption syndrome or other health conditions that affect nutrient absorption, discuss with your healthcare provider whether you need a higher dose of Folic Acid. 
  • Long-Term Use: If you are on long-term Folic Acid therapy, your doctor may recommend additional monitoring and supplementation with other B vitamins, particularly vitamin B12. 
  • Child Safety: Keep Folic Acid supplements out of reach of children; an accidental overdose in children can be dangerous. 
  • Storage Information: Keep Folic Acid at room temperature, away from light and moisture. 
  • Handling Instructions: If using the liquid form, carefully measure the dose using a special measuring device/spoon. 


Where is Folic Acid available in Hong Kong?

Folic Acid is an over-the-counter (OTC) medication that can be sold without a prescription. It is found in all chain drug stores, including Mannings and Watsons.  


Can you take too much Folic Acid?

No, taking too much can hide vitamin B12 deficiency symptoms and has other potential risks.

Should men take Folic Acid?

Men can take Folic Acid for its health benefits, although the recommended dosage may be lower than for women.

Is Folic Acid available for purchase over the counter?

Yes, Folic Acid can be purchased over the counter without a prescription. 

When to take Folic Acid morning or night?

Folic acid is generally considered safe and can be taken at any time of the day. There is no specific requirement for taking folic acid in the morning or at night. You can choose a time that is convenient for you and fits well with your routine. 

This website provides content related to drug use and medicine for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Do not use the information on this website to diagnose or treat a health problem or disease without consulting a qualified healthcare provider. The website's owners and contributors are not liable for any repercussions, adverse effects, or consequences resulting from the use of any medication or information provided herein.

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