Last updated on RxList: 4/21/2021
Drug Description

What is Metanx and how is it used?

Metanx is a prescription medicine used to treat the symptoms of Diabetic Peripheral Neuropathy. Metanx may be used alone or with other medications.

Metanx belongs to a class of drugs called Food, Supplements.

It is not known if Metanx is safe and effective in children.

What are the possible side effects of Metanx?

  • upset stomach,
  • vomiting,
  • loss of appetite,
  • abdominal pain,
  • diarrhea,
  • drowsiness,
  • headache, and
  • acne

Get medical help right away, if you have any of the symptoms listed above.

The most common side effects of Metanx include:

  • acne,
  • skin reactions,
  • allergic reactions,
  • sensitivity to sunlight,
  • nausea,
  • vomiting,
  • abdominal pain,
  • loss of appetite,
  • increased liver function test results,
  • numbness and tingling,
  • drowsiness,
  • nausea,
  • headaches,
  • diarrhea,
  • itching,
  • temporary skin rash, and
  • the feeling of swelling of the entire body

Tell the doctor if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of Metanx. For more information, ask your doctor or pharmacist.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


METANX® is a prescription medical food for use only under the supervision of a physician for the clinical dietary management of diabetic peripheral neuropathy and is specially formulated to meet the distinctive nutritional requirements for this condition.

Each METANX® capsule contains 3 mg of L-methylfolate Calcium (as Metafolin®)*, 90.314 mg of Algae-S Powder (Schizochytrium), 35 mg of Pyridoxal-5´-Phosphate and 2.0 mg of Methylcobalamin *CAS#151533-22-1


Silicified Microcrystalline Cellulose, Algae-S Powder [Schizochytrium Algal Oil (Vegetable Source), Glucose Syrup Solids, Mannitol, Sodium Caseinate (Milk), Soy Protein, High Oleic Sunflower Oil, 2% or less Sodium Ascorbate, Tricalcium Phosphate, Tetrasodium Diphosphate, Natural Flavors, Soy Lecithin, and Mixed Natural Tocopherols and Ascorbyl Palmitate (as antioxidants)], Pullulan, Pyridoxal 5’- Phosphate, L-methylfolate Calcium, Methylcobalamin, Titanium Dioxide (color), Magnesium Stearate (Vegetable Source), Caramel (color), Riboflavin USP, Shellac, Propylene Glycol USP. Contains Milk and Soy

METANX® capsules do not contain lactose, yeast or gluten.

METANX® Is A Prescription Medical Food For Use Only Under The Supervision Of A Physician

Medical foods are intended for a patient who has a limited or impaired capacity to ingest, digest, absorb, or metabolize ordinary foodstuffs or certain nutrients, or who has other special medically determined nutrient requirements, the dietary management of which cannot be achieved by the modification of the normal diet alone.1 This product is not an Orange Book product.


1. United States Food and Drug Administration Title 21 Code of Federal Regulations 101.9(j) (8).

Indications & Dosage


METANX® is indicated for the distinct nutritional requirements of individuals with endothelial dysfunction who present with loss of protective sensation and neuropathic pain associated with diabetic peripheral neuropathy.2-7

METANX® is indicated for the distinct nutritional requirements of patients with endothelial dysfunction and/or hyperhomocysteinemia who present with lower extremity ulceration(s).8-11


Recommended Use

The usual adult dose may be taken as one capsule twice daily (1 capsule B.I.D.); or two capsules once daily (2 capsules QD); or as directed under medical supervision.


METANX® is a prescription medical food for use only under the supervision of a physician.

METANX® Bottle of 90 Product Code # 00525-8049-90*. Use under medical supervision.

METANX® Bottle of 180 Product Code # 00525-8049-18*. Use under medical supervision.

Each METANX® capsule has an opaque caramel cap and opaque white body. It is imprinted with “Metanx” in red ink on the body.


Store at controlled room temperature 15°C to 30°C (59°F to 86°F) (See USP). Protect from heat, light and moisture.

*Alfasigma USA, Inc. does not represent these product codes to be National Drug Codes (NDC). Product codes are formatted according to standard industry practice, to meet the formatting requirements of pharmacy and health insurance computer systems.


2. Verhaar M.C., et al. Circulation 1998;97:237-241.

3. Van Etten R.W., et al. Diabetologia 2002;45:1004-1010.

4. Romerio S.C., et al. Atherosclerosis 2004;176:337-344.

5. Walker MJ Jr, et al. Rev Neurol Dis 2010;7(4):132-139.

6. Jacobs AM, Cheng D. J Diabetes Mellitus. 2013;3(3):134-138.

7. Li G. Beijing Methylcobal Clinical Trial Collaborative Group. Zhonghua Nei Ke Za Zhi 1999;38(1):14-17.

8. Ambrosch A. et al. Diabet Med. 2001;18:185-192.

9. Veves A., et al. Diabetes 1998;47:457-463.

10. Boykin J.V. Jr. Vascular Disease Management 2007;2(1):1-8.

11. Boykin J.V. Jr., Byalis C.Wounds 2006;18(4):101-116.

Distributed by: Alfasigma USA, Inc. Covington, LA 70433. Revised: Feb 2017


What is diabetic peripheral neuropathy? See Answer
Side Effects & Drug Interactions


Allergic reactions have been reported following the use of oral L-methylfolate Calcium.14 Acne, skin reactions, allergic reactions, photosensitivity, nausea, vomiting, abdominal pain, loss of appetite, increased liver function test results, paresthesia, somnolence, nausea and headaches have been reported with pyridoxal 5'-phosphate.15 Mild transient diarrhea, itching, transitory exanthema and the feeling of swelling of the entire body has been associated with methylcobalamin.16


No Information Provided


14. Natural Standard Research Collaboration (NIH). Folate (folic acid) Monograph 2009.

15. Alternative Medicine Review Vitamin B6 Monograph Volume 6, Number 1, 2001.

16. Natural Standard Research Collaboration (NIH). Vitamin B12Monograph 2009.

Warnings & Precautions


METANX® is a prescription medical food for use only under the supervision of a physician.



Folic acid, when administered in daily doses above 0.1mg, may obscure the detection of B12 deficiency (specifically, the administration of folic acid may reverse the hematological manifestations of B12 deficiency, including pernicious anemia, while not addressing the neurological manifestations). L-methylfolate Calcium may be less likely than folic acid to mask vitamin B12 deficiency.12,13 Folate therapy alone is inadequate for the treatment of a B12 deficiency.


12. B Akoglu, et al. European Journal of Clinical Nutrition (2007), 1-6.

13. Scott JM, et al.Lancet. 1981 2:337-340.

Overdosage & Contraindications


No Information Provided


METANX® is contraindicated in patients with known hypersensitivity to any of the components contained in this product.

Clinical Pharmacology


No Information Provided

Medication Guide


No information provided. Please refer to the WARNINGS and PRECAUTIONS sections.

FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Health Solutions From Our Sponsors