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

Nitro8 Ingredients & Drug Interactions

by ProPharm Performance

Nitro8 label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Nitro8 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

Nitro8 is a dietary supplement by ProPharm Performance with 3 active ingredients. Its ingredients are commonly taken for preventing neural tube birth defects, treating or preventing folate deficiency, supporting pregnancy health.Based on those ingredients, 59 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Folic Acid, Propionyl L-Carnitine HCl. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Nitro8 by ProPharm Performance

Ask about any prescription or over-the-counter medication and we check it for interactions with Nitro8 by ProPharm Performance — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Nitro8 by ProPharm Performance

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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Nitro8 has three active ingredients. Folic acid is a B vitamin used to correct folate deficiency and reduce birth defect risk.

Beta-alanine is an amino acid that some research suggests may support athletic and physical performance. Propionyl L-carnitine is a compound form of the nutrient carnitine, which has shown possible benefit for heart-related conditions and ulcerative colitis.

There are no inactive ingredients listed for this product.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Muscle growth, strength, energy, endurance and recovery.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle breakdown, Physical performance, Sarcopenia, Erectile dysfunction (ED), Intermittent claudication — and 4 related terms.
  • The strongest evidence on file: Propionyl-l-carnitine is rated "Possibly Effective" for Cardiovascular disease (CVD) (Natural Medicines).
  • Also on file: Propionyl-l-carnitine is rated "Possibly Effective" for Intermittent claudication.
  • Also on file: Beta-alanine is rated "Possibly Effective" for Athletic performance, Physical performance.

Folic acid in this product is effective for correcting folate deficiency and is likely effective for preventing methotrexate toxicity and neural tube birth defects; it's possibly effective for depression and cognitive concerns. Beta-alanine is possibly effective for athletic and physical performance, but evidence is insufficient to rate it for cognitive decline, COPD, cognitive function, or menopausal symptoms.

Propionyl L-carnitine is possibly effective for ulcerative colitis, congestive heart failure, angina, and cardiovascular disease.

The evidence, ingredient by ingredient Folic Acid Beta-alanine Propionyl-l-carnitine

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • 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 5 mg daily it may cause abdominal cramps, diarrhea, or rash; at 15 mg daily some people report bitter taste, confusion, hyperactivity, or sleep disturbances.

Serious side effects like seizures or liver injury are rare. Folic acid is recommended during pregnancy at standard prenatal doses and is considered safe while breastfeeding, though late-pregnancy use has been associated with increased childhood asthma risk in population studies.

Beta-alanine is generally well tolerated but commonly causes a harmless tingling sensation (paresthesia) and flushing, usually starting on the scalp. Safety data is insufficient for pregnancy and breastfeeding — the facts advise against use in both.

Propionyl L-carnitine is generally well tolerated for short-term use; common side effects include nausea, vomiting, diarrhea, and gastric pain. One trial reported bronchitis and back pain more often than placebo.

Safety has not been established in pregnancy or breastfeeding — avoid in both.

Side effects, ingredient by ingredient Folic Acid Beta-alanine Propionyl-l-carnitine

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?
  • 2 of the 3 matched ingredients can interact with medications — Propionyl-l-carnitine, Folic Acid.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 59 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.

Check your exact medications before taking this product if you use seizure preventers (phenobarbital, phenytoin, primidone), blood thinners (warfarin, acenocoumarol), cancer drugs (methotrexate, capecitabine, 5-fluorouracil), or thyroid hormone replacement. All of these have documented moderate-severity interactions with ingredients in Nitro8.

Check your own medication Run your meds through the checker above

The bottom line

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

Nitro8 is a performance supplement with research-supported roles for athletic output and some cardiovascular concerns. If you take a seizure medication, blood thinner, chemotherapy drug, or thyroid medication, talk to your pharmacist before starting — folic acid and propionyl L-carnitine can interfere with these.

Avoid it if you're pregnant or breastfeeding without talking to your doctor or pharmacist first.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 25, 2013.

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 Nitro8, straight from the product label.

Brand ProPharm Performance
Barcode (UPC) 0007282011
Net contents 90 Capsule(s)
Market status Off market
Date entered into DSLD Feb 25, 2013
DSLD ID 18072
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Male (18-50 Years)
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 Nitro8 by ProPharm Performance, 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:
3 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
3
UPC/BARCODE
0007282011
IngredientAmount% DV
Folic Acid600 mcg, 300 mcg--
Beta-Alanine1000 mg, 500 mg--
Propionyl L-Carnitine HCl4.5 g, 2.25 g--

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.
General Statements

Sustain Massive Muscle Pumps Increase Muscle Size & Strength Increase Energy & Endurance Enhance Fat Burning Reduce Lactic Acid Improve Muscle Recovery

Precautions

Warnings: Do not exceed the recommended dose.

Keep out of reach of children.

Consult your physician before using this dietary supplement. Do not use this product if you are at risk or are being treated for high blood pressure, kidney, thyroid, or psychiatric disease, difficulty urninating, prostate enlargement, anxiety, depression, seizure disorder, or stroke. DO NOT USE IF SEAL IS DAMAGED OR MISSING.

KEEP OUT OF REACH OF CHILDREN

Storage

STORE IN A COOL, DRY PLACE.

FDA Disclaimer Statement

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Suggested/Recommended/Usage/Directions

Serving Size: 3 Capsules Full Clinical Dose: 6 Capsules

Suggested Use: As a dietary supplement, take three (3) capsules two (2) times daily in divided doses.

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

See for yourself

Nitro8 by ProPharm Performance label

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

Nitro8 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 Nitro8 by ProPharm Performance

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 Capsule(s) Dosage formCapsule Servings per container3 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Folic Acid

Interacts with
40 drugs
600 mcg per serving

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 ta...

Folic Acid monograph & interactions

Beta-Alanine

No known
interactions
1000 mg per serving

Beta-alanine is an amino acid taken mostly by athletes to raise muscle carnosine, which may help buffer acid and reduce fatigue during short, high-int...

Beta-Alanine monograph & interactions

Propionyl L-Carnitine HCl

Interacts with
19 drugs
4.5 g per serving

Propionyl-l-carnitine is a form of the amino acid derivative carnitine that the body uses to help turn fat into energy, and it is studied mostly for c...

Propionyl L-Carnitine HCl monograph & interactions
Interaction report

Nitro8 by ProPharm Performance Drug Interactions

Want to check YOUR meds against Nitro8?

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
59Drugs
59 Moderate

Ingredients driving the most interactions

Folic Acid 40
Propionyl L-Carnitine HCl 19

Individual Drug Interactions

The ingredients in Nitro8 interact with 59 drugs. Click any drug to see the details.

2 of the 3 ingredients in Nitro8 interact with drugs. Each result below shows which ingredient is responsible. Folic Acid Propionyl L-Carnitine HCl

Each ingredient & the kinds of drugs it affects

For each ingredient in Nitro8 with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Folic Acid7 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
Folic Acid full monograph & interactions

Propionyl L-Carnitine HCl3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, propionyl-L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine, the parent compound of propionyl-L-carnitine, might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation when L-carnitine was taken with acenocoumarol. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product. It is unclear if such an interaction would also occur with propionyl-L-carnitine.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, acetyl-L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism. It is unclear if such an interaction would occur with propionyl-L-carnitine.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Theoretically, propionyl-L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine, the parent compound of propionyl-L-carnitine, might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with propionyl-L-carnitine and warfarin.

Likelihood Possible Evidence D
Propionyl L-Carnitine HCl full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Nitro8, from the product label.

ProPharm Performance

See all ProPharm Performance products
Name
PRO-PHARM PERFORMANCE
Web Address
www.ProPharmPerformance.com
Pharmacist Counseling Corner

Nitro8 by ProPharm Performance: Common Questions

Does Nitro8 by ProPharm Performance interact with any medications?
Yes. Based on its ingredients, Nitro8 has a known interaction with 59 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Nitro8 contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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.
Is folic acid in this product safe to take if I'm pregnant?
Folic acid is recommended during pregnancy at standard prenatal doses to help prevent birth defects. However, late-pregnancy use has been linked to increased childhood asthma risk in population studies. Talk to your doctor or midwife about the right dose and timing for you.
What's that tingling sensation I feel after taking beta-alanine?
That's paresthesia — a harmless pins-and-needles feeling caused by beta-alanine. It usually starts on your scalp within 20 minutes and spreads across your body, lasting about an hour. It's not dangerous, but it's annoying at higher doses.
Can I take Nitro8 while breastfeeding?
Folic acid is considered safe while breastfeeding at normal recommended doses. Beta-alanine and propionyl L-carnitine don't have enough safety data for breastfeeding — the facts advise against them. Talk to your pharmacist or doctor about whether this product is right for you.
I'm on levothyroxine for my thyroid. Can I take this?
Propionyl L-carnitine in this product may theoretically reduce how well thyroid hormone replacement works. You should talk to your pharmacist or doctor before starting Nitro8 to make sure it won't interfere with your medication.
Does this product actually help athletic performance?
Beta-alanine is possibly effective for athletic and physical performance based on current research. The evidence isn't conclusive, but some studies do show a benefit, especially for repeated high-intensity exercise.
What are the most common side effects?
Folic acid at higher doses can cause nausea, sleep problems, and irritability. Beta-alanine commonly causes tingling and flushing. Propionyl L-carnitine may cause nausea, vomiting, or diarrhea. All of these are mild for most people.

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

Not sure if Nitro8 is safe with your meds?

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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.

Nitro8 label
Go deeper

The Full Monographs Behind Nitro8’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 → Herb & supplement monograph

Beta-alanine

Beta-alanine is an amino acid taken mostly by athletes to raise muscle carnosine, which may help buffer acid and reduce fatigue during short, high-intensity exercise. The evidence is moderat...

Read the full Beta-alanine monograph → Herb & supplement monograph

Propionyl-l-carnitine

Interacts with 19 drugs

Propionyl-l-carnitine is a form of the amino acid derivative carnitine that the body uses to help turn fat into energy, and it is studied mostly for circulation problems like peripheral arte...

Read the full Propionyl-l-carnitine monograph →
Sources

Sources & How We Checked

Nitro8'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 81 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
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Duhra P. Treatment of gastrointestinal symptoms associated with methotrexate therapy for psoriasis. J Am Acad Dermatol 1993;28:466-9. PubMed
  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
  5. Lewis DP, Van Dyke DC, Willhite LA, et al. Phenytoin-folic acid interaction. Ann Pharmacother 1995;29:726-35. PubMed
  6. Berg MJ, Stumbo PJ, Chenard CA, et al. Folic acid improves phenytoin pharmacokinetics. J Am Diet Assoc 1995;95:352-6. PubMed
  7. Berg MJ, Fincham RW, Ebert BE, et al. Phenytoin pharmacokinetics: Before and after folic acid administration. Epilepsia 1992;33:712-20. PubMed
  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
  11. Dijkmans BA. Folate supplementation and methotrexate. Br J Rheumatol 1995;34:1172-4. PubMed
  12. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  13. Lambie DG, Johnson RH. Drugs and folate metabolism. Drugs 1985;30:145-55. PubMed
  14. Amer College of Rheumatology ad hoc committee on clinical guidelines. Guidelines for monitoring drug therapy in rheumatoid arthritis. Arthritis Rheum 1996;39:723-31. DOI
  15. Suitor CW, Bailey LB. Dietary folate equivalents: interpretation and application. J Am Diet Assoc 2000;100:88-94. PubMed
  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
  17. Sandoval M, Charbonnet RM, Okuhama NN, et al. Cat's claw inhibits TNFalpha production and scavenges free radicals: role in cytoprotection. Free Radic Biol Med 2000;29:71-78.
  18. Antony AC. Megaloblastic Anemias. In: Hoffman R, Benz Jr EJ, Shattil SJ, et al. Hematology: Basic Principles and Practice. 3rd ed. New York, NY: Churchill Livingstone 2000: 451-79.
  19. Reynolds EH. Neurological aspects of folate and vitamin B12 metabolism. Clin Haematol 1976;5:661-96. DOI
  20. Reynolds EH. Folate metabolism and anticonvulsant therapy. Proc R Soc Med 1974;67:68.
  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
  22. Van Delden C, Hirschel B. Folinic acid supplements to pyrimethamine-sulfadiazine for Toxoplasma encephalitis are associated with better outcome (letter). J Infect Dis 1996;173:1294-5. PubMed
  23. Schroder H, Clausen N, Ostergard E, Pressler T. Folic acid supplements in vitamin tablets: a determinant of hematological drug tolerance in maintenance therapy of childhood acute lymphoblastic leukemia. Ped Hematol Oncol 1986;3:241-7. PubMed
  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
  26. Bonaa KH, Njolstad I, Ueland PM, et al. NORVIT: Homocysteine lowering and cardiovascular events after acute myocardial infarction. N Enlg J Med 2006;354:1578-88. PubMed
  27. Lawson KA, Wright ME, Subar A, et al. Multivitamin use and risk of prostate cancer in the National Institutes of Health-AARP Diet and Health Study. J Natl Cancer Inst 2007;99:754-64. PubMed
  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.
  31. Ebbing M, Bonaa KH, Nygard O, et al. Cancer incidence and mortality after treatment with folic acid and vitamin B12. JAMA 2009;302:2119-26.
  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
  37. Hankey GJ, Eikelboom JW, Yi Q, et al. Treatment with B vitamins and incidence of cancer in patients with previous stroke or transient ischemic attack: Results of a randomized placebo-controlled trial. Stroke 2012;43(6):1572-7. PubMed
  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
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See these in context on the Propionyl-l-carnitine monograph →

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