Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

L-MethylFolate Ingredients & Drug Interactions

by Klaire Labs

L-MethylFolate label
See full label image
Capsule Category: Vitamin
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-MethylFolate against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

L-MethylFolate is a dietary supplement by Klaire Labs with 1 active ingredient. Its ingredients are commonly taken for preventing neural tube birth defects, treating or preventing folate deficiency, supporting pregnancy health.Based on those ingredients, 40 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Metafolin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against L-MethylFolate by Klaire Labs

Ask about any prescription or over-the-counter medication and we check it for interactions with L-MethylFolate by Klaire Labs — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of L-MethylFolate by Klaire Labs

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • “Folate” is listed as a grouped ingredient — the label gives one combined amount (1,700 mcg DFE) without saying how much of each component you get.

This product contains one active ingredient: Metafolin, a form of folic acid (also called folate or vitamin B9). The inactive ingredients are microcrystalline cellulose, a vegetarian capsule, L-leucine, cellulose, and silicon dioxide.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Folate supplement supporting health.
  • We looked for evidence on: Folate deficiency, Neural tube birth defects, Anemia, Fetal and premature infant mortality, Low birth weight, Abdominal wall defects — and 4 related terms.
  • The strongest evidence on file: Folic Acid is rated "Effective" for Folate deficiency (Natural Medicines).
  • Also on file: Folic Acid is rated "Likely Effective" for Neural tube birth defects.
  • Also on file: Folic Acid is rated "Possibly Ineffective" for Anemia, Pre-eclampsia, Fetal and premature infant mortality.

The evidence supports folic acid for treating folate deficiency and is likely effective for reducing methotrexate toxicity and preventing neural tube birth defects in pregnancy. It's possibly effective for depression, phenytoin-induced gingival hyperplasia (overgrowth of gum tissue caused by certain seizure medications), and cognitive impairment, though the data here is less complete.

The evidence, ingredient by ingredient Folic Acid

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Folic acid is generally well tolerated at recommended doses for most adults. At lower doses (under 1 mg daily), side effects are rare.

At 5 mg daily, some people report abdominal cramps, diarrhea, and rash. Higher doses (15 mg daily) can cause bitter taste, confusion, sleep problems, nausea, and irritability.

Rare serious effects with long-term use include seizures, liver injury, and cardiovascular issues. The safety data advises folic acid is recommended during pregnancy at standard prenatal doses to help prevent birth defects, and is considered safe at normal recommended doses while breastfeeding.

One caution: very high doses of folic acid can mask the symptoms of pernicious anemia (a vitamin B12 deficiency condition), delaying treatment and risking nerve damage — so don't self-treat suspected anemia without talking to your pharmacist first.

Side effects, ingredient by ingredient Folic Acid

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Folic Acid.
  • The most serious interaction on file is rated Moderate.
  • For scale: 40 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check if you take seizure medications (phenobarbital, phenytoin, primidone), cancer treatments (methotrexate, capecitabine, 5-fluorouracil), or pyrimethamine for infection — folic acid has Moderate interactions with all of these and may reduce their effectiveness or increase side effects.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product works well for folate deficiency and is likely helpful around pregnancy to prevent birth defects. If you take seizure medications, cancer drugs, or certain antimicrobials, check your specific medications before starting — folic acid can interfere with how they work.

Talk to your pharmacist about your medications and dosing.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 24, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about L-MethylFolate, straight from the product label.

Brand Klaire Labs
Barcode (UPC) 828054001015
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD May 24, 2023
DSLD ID 295225
Product type Vitamin
Supplement form Capsule
Dietary claims / uses Nutrient, All Other
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for L-MethylFolate by Klaire Labs, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
UPC/BARCODE
828054001015
IngredientAmount% DV
Folate1700 mcg DFE425%
Metafolin1000 mcg--

Other ingredients: Microcrystalline Cellulose, Vegetarian Capsule, L-Leucine, Cellulose, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Suggested Use: 1 capsule daily with food or as directed by a healthcare professional.

Formula

L-MethylFolate contains L-5-methyltetrahydrofolate (L-5-MTHF), the active, methylated form of folate, an essential B-vitamin. L-5-MTHF requires no additional metabolic steps to be used by the body, thus it is often the preferred choice for those with absorption or metabolic defects. Supplies 1 mg (1,700 mcg DFE) folate per capsule.

Brand IP Statement(s)

Metafolin Metafolin is a registered trademark of Merck KGaA, Darmstadt, Germany

SFI

Precautions

Do not use if shrinkwrap is broken or missing.

Caution: If you are pregnant, nursing, have a medical condition, or taking prescription drugs, consult your healthcare professional before using this product.

Keep out of reach of children.

Storage

Store in a cool, dry place (59 degrees F-85 degrees F) away from direct light.

Formulation

Produced under a strict quality management system in compliance with Good Manufacturing Practices (GMPs) and third-party quality certifications.

Free of the following common allergens: milk/casein, eggs, fish, shellfish, tree nuts, peanuts, wheat, gluten, soybeans and corn. Contains no artificial colors, flavors, or preservatives.

FDA Statement of Identity

Folate Supplement

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

L-MethylFolate by Klaire Labs label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

L-MethylFolate label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in L-MethylFolate by Klaire Labs

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Folate

1700 mcg DFE per serving

Other (inactive) ingredients: Microcrystalline Cellulose, Vegetarian Capsule, L-Leucine, Cellulose, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-MethylFolate by Klaire Labs Drug Interactions

Want to check YOUR meds against L-MethylFolate?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
40Drugs
40 Moderate

Ingredients driving the most interactions

Metafolin 40

Individual Drug Interactions

The ingredients in L-MethylFolate interact with 40 drugs. Click any drug to see the details.

1 of the 1 ingredient in L-MethylFolate interact with drugs. Each result below shows which ingredient is responsible. Metafolin

Each ingredient & the kinds of drugs it affects

For each ingredient in L-MethylFolate with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Metafolin7 drug types · 40 drugs

5-Fluorouracil

Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil.

Likelihood Possible Evidence D
Capecitabine (Xeloda)

Use of high-dose folic acid might contribute to capecitabine toxicity.
Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer. Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine.

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers. Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of phenobarbital and worsening seizure control. Monitor closely for increased seizure activity.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Folic acid might reduce serum levels of phenytoin in some patients.
Folic acid may be a cofactor in phenytoin metabolism. Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients. Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided. Note that phenytoin also reduces serum folate levels.

Likelihood Probable Evidence B
Primidone (Mysoline)

Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of primidone and worsening seizure control. Monitor closely for increased seizure activity. Note that primidone also reduces serum folate levels.

Likelihood Probable Evidence B
Pyrimethamine (Daraprim)

Folic acid might antagonize the effects of pyrimethamine.
Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated.

Likelihood Probable Evidence D
Metafolin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-MethylFolate, from the product label.

Klaire Labs

See all Klaire Labs products
Name
SFI USA
City
Reno
State
NV
ZipCode
89521
Web Address
Klaire.com
Pharmacist Counseling Corner

L-MethylFolate by Klaire Labs: Common Questions

Does L-MethylFolate by Klaire Labs interact with any medications?
Yes. Based on its ingredients, L-MethylFolate has a known interaction with 40 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-MethylFolate contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this while I'm pregnant?
Yes — folic acid is recommended during pregnancy at standard prenatal doses to help prevent birth defects. That said, late pregnancy use has been linked in population studies to a slightly increased risk of childhood asthma. The safest approach is to take it before pregnancy or early in pregnancy, and talk with your doctor about the timing and dose that's right for you.
Is this safe while breastfeeding?
Yes, folic acid is considered safe at normal recommended doses while breastfeeding.
What dose should I take?
That depends on why you're taking it and your individual health. At doses under 1 mg daily, side effects are very rare. Higher doses (5–15 mg daily) carry a real risk of nausea, sleep problems, and confusion. Your pharmacist can help you figure out the right dose for your situation.
Can this help my depression?
Folic acid is possibly effective for depression, though the evidence isn't as strong as it is for treating folate deficiency. It's worth discussing with your doctor if you're considering it as part of your treatment plan.
What if I have anemia?
Don't self-treat anemia with folic acid alone — high-dose folic acid can mask the symptoms of pernicious anemia (a vitamin B12 deficiency), which can lead to nerve damage if it goes untreated. See your pharmacist or doctor first so they can figure out what kind of anemia you have.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-MethylFolate label
Go deeper

The Full Monographs Behind L-MethylFolate’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Folic Acid

Interacts with 40 drugs

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when taken before and during early pregnancy. I...

Read the full Folic Acid monograph →
Sources

Sources & How We Checked

L-MethylFolate's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 56 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Folic Acid 56 references
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  3. Morgan SL, Baggott JE, Vaughn WH, et al. Supplementation with folic acid during methotrexate therapy for rheumatoid arthritis. A double-blind, placebo-controlled trial. Ann Intern Med 1994;121:833-41. PubMed
  4. Froscher W, Maier V, Laage M, et al. Folate deficiency, anticonvulsant drugs, and psychiatric morbidity. Clin Neuropharmacol 1995;18:165-82. PubMed
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  8. Shafer RB, Nuttall FQ. Calcium and folic acid absorption in patients taking anticonvulsant drugs. J Clin Endocrinol Metab 1975;41:1125-9. PubMed
  9. Leeb BF, Witzmann G, Ogris E, et al. Folic acid and cyanocobalamin levels in serum and erythrocytes during low-dose methotrexate therapy of rheumatoid arthritis and psoriatic arthritis patients. Clin Exp Rheumatol 1995;13:459-63.
  10. Morgan SL, Baggott JE, Lee JY, Alarcón GS. Folic acid supplementation prevents deficient blood folate levels and hyperhomocysteinemia during longterm, low dose methotrexate therapy for rheumatoid arthritis: implications for cardiovascular disease preventi
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  16. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
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  19. Reynolds EH. Neurological aspects of folate and vitamin B12 metabolism. Clin Haematol 1976;5:661-96. DOI
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  21. Ortiz Z, Shea B, Suarez Almazor M, et al. Folic acid and folinic acid for reducing side effects in patients receiving methotrexate for rheumatoid arthritis (Cochrane Review). Cochrane Database Syst Rev 2000;2:CD000951. PubMed
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  24. Lange H, Suryapranata H, De Luca G, et al. Folate therapy and in-stent restenosis after coronary stenting. N Engl J Med 2004;350:2673-81. PubMed
  25. Morris MC, Evans DA, Bienias JL, et al. Dietary folate and vitamin B12 intake and cognitive decline among community-dwelling older persons. Arch Neurol 2005;62:641-5. PubMed
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  28. Figueiredo JC, Grau MV, Haile RW, et al. Folic acid and risk of prostate cancer: Results from a randomized clinical trial. J Natl Cancer Inst 2009;101:432-5. PubMed
  29. Clippe C, Freyer G, Milano G, Trillet-Lenoir V. Lethal toxicity of capecitabine due to abusive folic acid prescription. Clin Oncol (R Coll Radiol) 2003;15:299-300. PubMed
  30. Bedford Laboratories. Leucovorin calcium [package insert]. Bedford, OH. September 2008. Available at: http://www.bedfordlabs.com/BedfordLabsWeb/products/inserts/LCV-P02.pdf.
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  32. Haberg, S. E., London, S. J., Stigum, H., Nafstad, P., and Nystad, W. Folic acid supplements in pregnancy and early childhood respiratory health. Arch Dis.Child 2009;94(3):180-184. PubMed
  33. Whitrow, M. J., Moore, V. M., Rumbold, A. R., and Davies, M. J. Effect of supplemental folic acid in pregnancy on childhood asthma: a prospective birth cohort study. Am J Epidemiol. 12-15-2009;170(12):1486-1493. PubMed
  34. Collin, S. M., Metcalfe, C., Refsum, H., Lewis, S. J., Zuccolo, L., Smith, G. D., Chen, L., Harris, R., Davis, M., Marsden, G., Johnston, C., Lane, J. A., Ebbing, M., Bonaa, K. H., Nygard, O., Ueland, P. M., Grau, M. V., Baron, J. A., Donovan, J. L., Nea
  35. Baggott, J. E., Oster, R. A., and Tamura, T. Meta-analysis of cancer risk in folic acid supplementation trials. Cancer Epidemiol. 2012;36(1):78-81. PubMed
  36. Fonseca VA, Lavery LA, Thethi TK, et al. Metanx in type 2 diabetes with peripheral neuropathy: A randomized trial. Am J Med 2013;126(2):141-9. PubMed
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  38. Taneja S, Strand TA, Kumar T, et al. Folic acid and vitamin B-12 supplementation and common infections in 6-30-mo-old children in India: a randomized placebo-controlled trial. Am J Clin Nutr 2013;98(3):731-7. PubMed
  39. van Wijngaarden JP, Swart KM, Enneman AW, et al. Effect of daily vitamin B-12 and folic acid supplementation on fracture incidence in elderly individuals with an elevated plasma homocysteine concentration: B-PROOF, a randomized controlled trial. Am J Clin
  40. Qin X, Fan F, Cui Y, Chen F, Chen Y, Cheng X, Li Y, Wang B, Xu X, Xu X, Huo Y, Wang X. Folic acid supplementation with and without vitamin B6 and revascularization risk: a meta-analysis of randomized controlled trials. Clin Nutr. 2014;33(4):603-12. PubMed
  41. Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ. Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013;98(5):1272-81. PubMed
  42. Matsubara S, Imai K, Murayama K, Higashizawa T. Severe liver dysfunction during nausea and vomiting of pregnancy: folic acid supplement as a suggested culprit. J Obstet Gynaecol. 2012;32(7):701-2. PubMed
  43. Qin X, Cui Y, Shen L, Sun N, Zhang Y, Li J, Xu X, Wang B, Xu X, Huo Y, Wang X. Folic acid supplementation and cancer risk: a meta-analysis of randomized controlled trials. Int J Cancer. 2013 1;133(5):1033-41. PubMed
  44. Tio M, Andrici J, Cox MR, Eslick GD. Folate intake and the risk of prostate cancer: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis. 2014;17(3):213-9. PubMed
  45. Tomaszewski JJ, Richman EL, Sadetsky N, O'Keefe DS, Carroll PR, Davies BJ, Chan JM. Impact of folate intake on prostate cancer recurrence following definitive therapy: data from CaPSURE. J Urol. 2014;191(4):971-6. PubMed
  46. Valera-Gran D, García de la Hera M, Navarrete-Muñoz EM, Fernandez-Somoano A, Tardón A, Julvez J, Forns J, Lertxundi N, Ibarluzea JM, Murcia M, Rebagliato M, Vioque J; Infancia y Medio Ambiente (INMA) Project. Folic acid supplements during pregnancy and ch
  47. Van Der Woude DA, De Vries J, Van Wijk EM, Verzijl JM, Pijnenborg JM. A randomized controlled trial examining the addition of folic acid to iron supplementation in the treatment of postpartum anemia. Int J Gynaecol Obstet. 2014;126(2):101-5. PubMed
  48. Vila-Nova C, Wehby GL, Queirós FC, Chakraborty H, Félix TM, Goco N, Moore J, Gewehr EV, Lins L, Affonso CM, Murray JC. Periconceptional use of folic acid and risk of miscarriage - findings of the Oral Cleft Prevention Program in Brazil. J Perinat Med. 201 PubMed
  49. Vollset SE, Clarke R, Lewington S, Ebbing M, Halsey J, Lonn E, Armitage J, Manson JE, Hankey GJ, Spence JD, Galan P, Bønaa KH, Jamison R, Gaziano JM, Guarino P, Baron JA, Logan RF, Giovannucci EL, den Heijer M, Ueland PM, Bennett D, Collins R, Peto R; B-V
  50. Wehby GL, Félix TM, Goco N, Richieri-Costa A, Chakraborty H, Souza J, Pereira R, Padovani C, Moretti-Ferreira D, Murray JC. High dosage folic acid supplementation, oral cleft recurrence and fetal growth. Int J Environ Res Public Health. 2013 4;10(2):590-6 PubMed
  51. Fanidi A, Carreras-Torres R, Larose TL, et al. Is high vitamin B12 status a cause of lung cancer? Int J Cancer. 2019 Sep 15;145(6):1499-1503. PubMed
  52. Liu J, Li Z, Ye R, Liu J, Ren A. Periconceptional folic acid supplementation and risk of parent-reported asthma in children at 4-6 years of age. ERJ Open Res. 2020;6(1):00250-2019. PubMed
  53. Houghton LA, Sherwood KL, Pawlosky R, Ito S, O'Connor DL. [6S]-5-Methyltetrahydrofolate is at least as effective as folic acid in preventing a decline in blood folate concentrations during lactation. Am J Clin Nutr. 2006 Apr;83(4):842-50. PubMed
  54. Houghton LA, Yang J, O'Connor DL. Unmetabolized folic acid and total folate concentrations in breast milk are unaffected by low-dose folate supplements. Am J Clin Nutr. 2009 Jan;89(1):216-20. PubMed
  55. Chan SL, Chan AWH, Mo F, et al. Association Between Serum Folate Level and Toxicity of Capecitabine During Treatment for Colorectal Cancer. Oncologist. 2018 Dec;23(12):1436-1445. PubMed
  56. Sarris J, Ravindran A, Yatham LN, et al. Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety T

See these in context on the Folic Acid monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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