About folic acid
Vitamin B9 (folate) supplement
Used for
- Treats and prevents folate-deficiency anaemia
- Prevents neural tube defects before and during early pregnancy
- Prevents deficiency in people with increased folate needs
Usual adult dose
Usually 5 mg once daily for folate-deficiency anaemia; pregnancy prevention commonly uses 400 micrograms daily.
Usual dose in children
For folate-deficiency anaemia, often 5 mg once daily; dose varies by age and cause.
Common side effects
- Usually well tolerated
- Occasional nausea, bloating, or reduced appetite
- Rare allergic reactions, including rash or breathing difficulty
Important warnings
- Vitamin B12 deficiency should be assessed; folic acid can mask its blood abnormalities while nerve damage progresses.
- Seek the cause of folate deficiency, which may need additional treatment.
- The dose for pregnancy prevention differs for people at higher risk.
Pregnancy
Generally recommended before conception and during early pregnancy to reduce neural tube defects; higher-risk dosing requires clinical assessment.
Breastfeeding
Generally compatible with breastfeeding at usual doses.
Interactions
- Methotrexate and some cancer medicines may interact; effects depend on the indication.
- Some anti-seizure medicines, including phenytoin, may interact.
- Sulfasalazine and trimethoprim can affect folate levels or action.
- Chloramphenicol may reduce response to folic acid in some people.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.