Major interaction on record — check this product against your medications before combining. Based on 6 of 15 ingredients. Check your meds →
Dietary supplement

Extreme Instant EAA Natural Flavour Ingredients & Drug Interactions

by Body Attack

Extreme Instant EAA Natural Flavour label
See full label image
Powder Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Extreme Instant EAA Natural Flavour 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: Major

Extreme Instant EAA Natural Flavour is a dietary supplement by Body Attack with 15 active ingredients. Its ingredients are commonly taken for morning sickness in pregnancy, premenstrual syndrome (pms), preventing or treating b6 deficiency.Based on those ingredients, 579 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Tryptophan, Vitamin B6, L-Phenylalanine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Extreme Instant EAA Natural Flavour by Body Attack

Ask about any prescription or over-the-counter medication and we check it for interactions with Extreme Instant EAA Natural Flavour by Body Attack — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Extreme Instant EAA Natural Flavour by Body Attack

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 12 of its 12 active ingredients.
  • “Total Essential Amino Acids” is listed as a grouped ingredient — the label gives one combined amount (9,461 mg) without saying how much of each component you get.

Extreme Instant EAA Natural Flavour contains 12 active ingredients, primarily essential amino acids (L-methionine, L-phenylalanine, L-isoleucine, L-valine, L-lysine, L-threonine, L-tryptophan, and L-leucine) plus vitamin B6. These amino acids are building blocks your body uses to make and repair muscle and other tissues.

The product also lists fat and salt among its active components. It contains several inactive ingredients—maltodextrin, lecithin, and some amino acid salts—that serve as fillers and stabilizers.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Essential amino acids for training and protein support.
  • We looked for evidence on: Athletic performance, Muscle strength, Muscle recovery, Exercise performance, Protein synthesis, Amino acid supplementation.
  • The closest evidence on file: Lysine is rated "Insufficient Reliable Evidence To Rate" for Athletic performance (Natural Medicines).
  • Also on file: Lysine is rated "Insufficient Reliable Evidence To Rate" for Muscle strength.
  • Also on file: L-tryptophan is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.

The effectiveness of this EAA blend depends on which ingredient you're asking about. Vitamin B6 is effective for sideroblastic anemia and vitamin B6 deficiency, and is likely effective for high homocysteine levels; it's possibly effective for pregnancy-related nausea.

L-phenylalanine is possibly effective for vitiligo but possibly ineffective for ADHD. L-lysine is possibly effective for cold sores.

L-methionine is possibly effective for neural tube birth defects in pregnancy. L-tryptophan, L-threonine, and the other amino acids lack established evidence for the conditions the product might be marketed for—the facts we hold show insufficient or no data to rate them.

The evidence, ingredient by ingredient Vitamin B6 Methionine Phenylalanine Lysine Threonine L-tryptophan

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 6 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

At normal amounts, most of these ingredients are generally well tolerated. Vitamin B6 is safe at standard supplement doses but can cause nerve damage (sensory neuropathy) at very high doses taken over time—the risk rises sharply above 1000 mg daily.

L-tryptophan can cause drowsiness, headache, nausea, and diarrhea; it has a history of contamination (a 1989 contamination scare caused over 1500 cases of a serious nerve disorder, though that was traced to one manufacturer). L-phenylalanine commonly causes anxiety, insomnia, headache, and heartburn.

L-lysine may cause stomach upset and abdominal pain at higher doses. L-methionine can lower blood pressure and increase a heart-risk marker called homocysteine.

L-threonine may cause headache or mild digestive upset. Pregnancy and breastfeeding safety varies by ingredient: L-phenylalanine should be avoided in both, L-tryptophan should be avoided in both, L-methionine is likely safe in pregnancy but breastfeeding safety is unknown, and L-lysine and L-threonine lack studied safety data in pregnancy and breastfeeding—talk with your doctor or pharmacist.

Side effects, ingredient by ingredient Vitamin B6 Methionine Phenylalanine Lysine Threonine L-tryptophan

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 5 of the 6 matched ingredients can interact with medications — Lysine, L-tryptophan, Phenylalanine, Vitamin B6, Threonine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 579 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 with your pharmacist if you take levodopa (Major), CNS depressants like sedatives or opioids (Major), NMDA antagonists like memantine (Major), serotonergic drugs including antidepressants (Moderate), seizure medications like phenobarbital or phenytoin (Moderate), blood-pressure medications (Moderate), amiodarone for heart rhythm (Moderate), baclofen for muscle spasticity (Moderate), MAOIs for depression (Moderate), or 5-HT4 agonists for digestive issues (Minor).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

This is an amino acid and B-vitamin supplement aimed at muscle support. If you take levodopa for Parkinson disease, are on seizure medications, take CNS depressants or antidepressants, or use any heart or nerve medication, check your exact medications with the tool on this page before starting.

Anyone with PKU (phenylketonuria) should avoid it. Speak with your pharmacist about whether it fits your health situation.

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

Assessment coverage: 6 of 12 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 24, 2025.

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 Extreme Instant EAA Natural Flavour, straight from the product label.

Brand Body Attack
Barcode (UPC) 4250350541463
Net contents 500 Gram(s)
Market status On market
Date entered into DSLD Jul 24, 2025
DSLD ID 334231
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, All Other
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Dairy Free, Sugar 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 Extreme Instant EAA Natural Flavour by Body Attack, 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:
14 Gram(s)
Maximum serving Sizes:
14 Gram(s)
Servings per container
35
UPC/BARCODE
4250350541463
IngredientAmount% DV
Vitamin B60.5 mg35%
L-Methionine900 mg--
Protein9.5 Gram(s)--
Carbohydrates4 Gram(s)--
Energy51 Kcal(s)--
Fat0.1 Gram(s)--
Total Essential Amino Acids9461 mg--
L-Phenylalanine1005 mg--
Saturated Fatty Acids0.1 Gram(s)--
Sugar0.1 Gram(s)--
Salt0.01 Gram(s)--
L-Isoleucine1229 mg--
L-Valine1229 mg--
L-Lysine1500 mg--
L-Threonine900 mg--
L-Tryptophan240 mg--
L-Leucine2458 mg--

Other ingredients: Maltodextrin, L-Leucine, L-Lysine Hydrochloride, L-Phenylalanine, L-Methionine, L-Threonine, L-Tryptophan, Lecithin

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

Recommended dosage: On training days, mix 14 g (1 scoop) in 350 mL cold water and consume before, during or after training once a day. On non-training days one serving in the morning. Note: For a better solubility shake for 30 seconds in a shaker.

Precautions

Do not exceed the recommended daily dosage.

Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Keep out of reach of small children.

FDA Statement of Identity

Food supplement with sweeteners.

Formula

Food supplement with sweeteners. Highly concentrated essential amino acids in powder form with vitamin B6. Flavour: Natural.

High dose premium EAA with vitamin B6

Storage

If kept unopened in a cool, dry place, best before end of/lot no.: see bottom. Once opened, consume quickly. Keep away from direct heat and light.

Seals/Symbols

Made in Germany

Formulation

V Vegan

Sugar free Lactose free

General Statements

%NRV % of Nutrient Reference Values

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

See for yourself

Extreme Instant EAA Natural Flavour by Body Attack label

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

Extreme Instant EAA Natural Flavour 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 Extreme Instant EAA Natural Flavour by Body Attack

These are the 15 active ingredients this product is made of. Select any to open its full monograph.

Serving size14 Gram(s) Dosage formPowder Servings per container35 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.

Vitamin B6

Interacts with
210 drugs
0.5 mg per serving

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

Protein

9.5 Gram(s) per serving

Carbohydrates

4 Gram(s) per serving
  • › Sugar

Energy

51 Kcal(s) per serving

Fat

0.1 Gram(s) per serving

Total Essential Amino Acids

9461 mg per serving

Saturated Fatty Acids

0.1 Gram(s) per serving

Salt

0.01 Gram(s) per serving

Other (inactive) ingredients: Maltodextrin, L-Leucine, L-Lysine Hydrochloride, L-Phenylalanine, L-Methionine, L-Threonine, L-Tryptophan, Lecithin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Extreme Instant EAA Natural Flavour by Body Attack Drug Interactions

Want to check YOUR meds against Extreme Instant EAA Natural Flavour?

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
579Drugs
256 Major 323 Moderate

Ingredients driving the most interactions

L-Tryptophan 394
Vitamin B6 210
L-Phenylalanine 16
L-Threonine 3
L-Lysine 1

Individual Drug Interactions

The ingredients in Extreme Instant EAA Natural Flavour interact with 579 drugs. Click any drug to see the details.

5 of the 15 ingredients in Extreme Instant EAA Natural Flavour interact with drugs. Each result below shows which ingredient is responsible. L-Tryptophan Vitamin B6 L-Phenylalanine L-Threonine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Extreme Instant EAA Natural Flavour 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.

L-Tryptophan2 drug types · 394 drugs

Cns Depressants

Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Clinical research shows that L-tryptophan can cause fatigue and drowsiness.

Likelihood Probable Evidence B
Serotonergic Drugs

Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
L-tryptophan is a precursor to serotonin. Theoretically, combining serotonergic drugs with L-tryptophan might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders.

Likelihood Possible Evidence D
L-Tryptophan full monograph & interactions

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & interactions

L-Phenylalanine3 drug types · 16 drugs

Levodopa

Phenylalanine, especially in high doses, can reduce the effectiveness of levodopa.
Phenylalanine competes with levodopa for carrier-mediated transport into the brain. The resulting reduction in levels of levodopa in the brain can exacerbate tremor, rigidity, and the "on-off" phenomenon in patients with Parkinson disease.

Likelihood Probable Evidence B
Baclofen

Concomitant intake of phenylalanine may reduce the intestinal absorption of baclofen.
Phenylalanine and baclofen share the same intestinal carrier for absorption; phenylalanine competitively inhibits the absorption of baclofen, reducing its plasma levels.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of L-phenylalanine and non-selective MAOIs might increase the risk of hypertensive crisis.
L-phenylalanine is metabolized to tyrosine. Some evidence suggests that L-phenylalanine, given with the non-selective MAOI pargyline, might prevent the elimination of tyramine, increasing the risk of hypertensive crisis. However, this was not reported in a small number of patients when using L-phenylalanine with the partially selective MAO-B inhibitor, selegiline.

Likelihood Possible Evidence D
L-Phenylalanine full monograph & interactions

L-Threonine1 drug type · 3 drugs

Nmda Antagonists

Theoretically, threonine might decrease the effects of NMDA antagonists.
Threonine increases central nervous system (CNS) glycine levels. Glycine seems to bind a site on NMDA receptors and enhance the activity of the receptors.

Likelihood Likely Evidence B
L-Threonine full monograph & interactions

L-Lysine1 drug type · 1 drug

5-Ht4 Agonists

Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Animal research suggests that L-lysine is a partial serotonin receptor 4 (5-HT4) antagonist and inhibits diarrhea induced by the 5-HT4 agonist, 5-hydroxytryptophane.

Likelihood Unlikely Evidence D
L-Lysine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Extreme Instant EAA Natural Flavour, from the product label.

Body Attack

See all Body Attack products
Name
Body Attack Sports Nutrition GmbH & Co. KG
Street Address
Schnackenburgalle 217-223
City
Hamburg
ZipCode
22525
Web Address
www.body-attack.com
Pharmacist Counseling Corner

Extreme Instant EAA Natural Flavour by Body Attack: Common Questions

Does Extreme Instant EAA Natural Flavour by Body Attack interact with any medications?
Yes. Based on its ingredients, Extreme Instant EAA Natural Flavour has a known interaction with 579 medications, including 256 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Extreme Instant EAA Natural Flavour contains 15 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.
Can I take this if I'm pregnant or breastfeeding?
It depends on the ingredient. L-phenylalanine should be avoided in both pregnancy and breastfeeding. L-tryptophan should also be avoided in both. L-methionine is likely safe in pregnancy but breastfeeding safety is not well studied. L-lysine and L-threonine lack enough safety data in pregnancy and breastfeeding. Talk with your doctor or pharmacist for personalized advice—don't skip it based on this product alone.
What's an EAA, and why would I take it?
EAA stands for essential amino acids—compounds your body needs to build and repair muscle, skin, and other tissues. Your body can't make them, so you get them from food or supplements. Athletes and active people sometimes use them to support muscle.
Can this cause nerve damage?
Vitamin B6 in this product can damage nerves (sensory neuropathy) if taken in very high doses over time—mainly at doses above 1000 mg daily. At the levels in a typical EAA powder, this is unlikely, but it's worth mentioning if you take B6 from multiple sources.
Will this make me sleepy?
L-tryptophan in here can cause drowsiness and fatigue in some people. If you're sensitive or take other medications that make you drowsy, you might notice extra tiredness—that's a reason to discuss it with your pharmacist first.
Does it have any fillers?
Yes, it contains inactive ingredients including maltodextrin and lecithin, which are binders and stabilizers to hold the powder together and improve texture.
What does vitamin B6 do in this product?
Vitamin B6 plays a role in amino acid metabolism and nerve function. It's proven effective for B6 deficiency and certain blood disorders, and possibly helpful for pregnancy-related nausea, but most of the benefit from this product comes from the amino acids themselves.

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

Not sure if Extreme Instant EAA Natural Flavour is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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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.

Extreme Instant EAA Natural Flavour label
Go deeper

The Full Monographs Behind Extreme Instant EAA Natural Flavour’s Ingredients

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

Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph → Herb & supplement monograph

Methionine

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a normal diet, and supplements are generally no...

Read the full Methionine monograph → Herb & supplement monograph

Phenylalanine

Interacts with 16 drugs

Phenylalanine is an essential amino acid the body uses to make brain chemicals like dopamine and norepinephrine. Some people take it for mood, vitiligo, or pain, but the evidence is mostly l...

Read the full Phenylalanine monograph → Herb & supplement monograph

Lysine

Interacts with 1 drug

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to try to prevent or shorten cold sores, but...

Read the full Lysine monograph → Herb & supplement monograph

Threonine

Interacts with 3 drugs

Threonine is an essential amino acid your body needs but cannot make, so you must get it from food or supplements. Most people get plenty from a normal diet, and high-quality evidence for ta...

Read the full Threonine monograph → Herb & supplement monograph

L-tryptophan

Interacts with 394 drugs

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for supplement use is limited and mixed, and...

Read the full L-tryptophan monograph →
Sources

Sources & How We Checked

Extreme Instant EAA Natural Flavour'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 96 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.

Vitamin B6 32 references
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Geerling BJ, Dagnelie PC, Badart-Smook A, et al. Diet as a risk factor for the development of ulcerative colitis. Am J Gastroenterol 2000;95:1008-13. PubMed
  4. South M. Neonatal seizures after pyridoxine use -- reply. Lancet 1999;354:2083. PubMed
  5. 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
  6. Baxter P, Aicardi J. Neonatal seizures after pyridoxine use. Lancet 1999;354:2082-3. PubMed
  7. Bendich A, Cohen M. Vitamin B6 safety issues. Ann N Y Acad Sci 1990;585:321-30.
  8. Schaumburg H, Kaplan J, Windebank A. Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl J Med 1983;309:445-8. PubMed
  9. Gordon N. Pyridoxine dependency: an update. Dev Med Child Neurol 1997;39:63-5. PubMed
  10. Lewis PJ. Pain in the hand and wrist. Pyridoxine supplements may help patients with carpal tunnel syndrome. BMJ 1995;310:1534. PubMed
  11. Kaufman G. Pyridoxine against amiodarone-induced photosensitivity (letter). Lancet 1984;1:51-2. PubMed
  12. Mulrow JP, Mulrow CD, McKenna WJ. Pyridoxine and amiodarone-induced photosensitivity. Ann Intern Med 1985;103:68-9. PubMed
  13. Kawada A, Kashima A, Shiraishi H, et al. Pyridoxine-induced photosensitivity and hypophosphatasia. Dermatology 2000;201:356-60.. PubMed
  14. Vasile A, Goldberg R, Kornberg B. Pyridoxine toxicity: report of a case. J Am Osteopath Assoc 1984;83:790-1. DOI
  15. Hansson O, Sillanpaa M. Pyridoxine and serum concentration of phenytoin and phenobarbitone. Lancet 1976;1:256. DOI
  16. Jansen T, Romiti R, Kreuter A, Altmeyer P. Rosacea fulminans triggered by high-dose vitamins B6 and B12. J Eur Acad Dermatol Venereol 2001;15:484-5..
  17. Chittumma P, Kaewkiattikun K, Wiriyasiriwach B. Comparison of the effectiveness of ginger and vitamin B6 for treatment of nausea and vomiting in early pregnancy: a randomized double-blind controlled trial. J Med Assoc Thai 2007;90:15-20.
  18. Hatzitolios, A., Iliadis, F., Katsiki, N., and Baltatzi, M. Is the anti-hypertensive effect of dietary supplements via aldehydes reduction evidence based? A systematic review. Clin Exp.Hypertens. 2008;30(7):628-639. PubMed
  19. Vasdev, S., Ford, C. A., Parai, S., Longerich, L., and Gadag, V. Dietary vitamin B6 supplementation attenuates hypertension in spontaneously hypertensive rats. Mol.Cell Biochem. 1999;200(1-2):155-162.
  20. de, Vogel S., Dindore, V., van, Engeland M., Goldbohm, R. A., van den Brandt, P. A., and Weijenberg, M. P. Dietary folate, methionine, riboflavin, and vitamin B-6 and risk of sporadic colorectal cancer. J Nutr 2008;138(12):2372-2378. PubMed
  21. Hagen, I., Nesheim, B. I., and Tuntland, T. No effect of vitamin B-6 against premenstrual tension. A controlled clinical study. Acta Obstet.Gynecol.Scand. 1985;64(8):667-670. PubMed
  22. Aybak, M., Sermet, A., Ayyildiz, M. O., and Karakilcik, A. Z. Effect of oral pyridoxine hydrochloride supplementation on arterial blood pressure in patients with essential hypertension. Arzneimittelforschung. 1995;45(12):1271-1273.
  23. Lal, K. J., Dakshinamurti, K., and Thliveris, J. The effect of vitamin B6 on the systolic blood pressure of rats in various animal models of hypertension. J Hypertens. 1996;14(3):355-363. PubMed
  24. Lauritzen CH, Reuter HD, Repges R, Bohnert K, and Schmidt U. Treatment of premenstrual tension syndrome with Vitex agnus castus. Controlled, double-blind study versus pyridoxine. Phytomed 1997;4(3):183-189. PubMed
  25. 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
  26. 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
  27. Hoyer-Kuhn H, Kohbrok S, Volland R, Franklin J, Hero B, Beck BB, Hoppe B. Vitamin B6 in primary hyperoxaluria I: first prospective trial after 40 years of practice. Clin J Am Soc Nephrol. 2014 Mar;9(3):468-77. PubMed
  28. Mahmoud A, Tabassum S, Al Enazi S, et al. Amelioration of levetiracetam-induced behavioral side effects by pyridoxine. A randomized double blind controlled study. Pediatr Neurol 2021;119:15-21. PubMed
  29. Gupta M, Gallante B, Bamberger JN, et al. Prospective randomized evaluation of idiopathic hyperoxaluria treatments. J Endourol 2021;35(12):1844-1851. PubMed
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Methionine 12 references
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Phenylalanine 23 references
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  23. Katoulis AC, Alevizou A, Bozi E, et al. A randomized, double-blind, vehicle-controlled study of a preparation containing undecylenoyl phenylalanine 2% in the treatment of solar lentigines. Clin Exp Dermatol 2010;35(5):473-6. PubMed

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Lysine 7 references
  1. Thein DJ, Hurt WC. Lysine as a prophylactic agent in the treatment of recurrent herpes simplex labialis. Oral Surg Oral Med Oral Pathol 1984;58:659-66. PubMed
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  4. Milman N, Scheibel J, Jessen O. Lysine prophylaxis in recurrent herpes simplex labialis: a double-blind, controlled crossover study. Acta Derm Venereol 1980;60:85-7.
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Threonine 4 references
  1. Tandan R, Bromberg MB, Forshew D, et al. A controlled trial of amino acid therapy in amyotrophic lateral sclerosis: I. Clinical, functional, and maximum isometric torque data. Neurology 1996;47:1220-6. PubMed
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L-tryptophan 18 references
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  2. Devoe LD, Castillo RA, Searle NS. Maternal dietary substrates and human fetal biophysical activity. The effects of tryptophan and glucose on fetal breathing movements. Am J Obstet Gynecol 1986;155:135-9. DOI
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  4. U. S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Nutritional Products, Labeling, and Dietary Supplements. Information Paper on L-Tryptophan and 5-hydroxy-L-tryptophan, February 2001.
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  14. Horwitz RI, Daniels SR. Bias or biology: evaluating the epidemiologic studies of L-tryptophan and the eosinophilia-myalgia syndrome. J Rheumatol Suppl 1996;46:60-72.
  15. Shapiro S. Epidemiologic studies of the association of L-tryptophan with the eosinophilia-myalgia syndrome: a critique. J Rheumatol Suppl 1996;46:44-58.
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  18. Ullrich SS, Fitzgerald PCE, Giesbertz P, Steinert RE, Horowitz M, Feinle-Bisset C. Effects of intragastric administration of tryptophan on the blood glucose response to a nutrient drink and energy intake, in lean and obese men. Nutrients 2018;10(4). pii: PubMed

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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.

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