Major interaction on record — check this product against your medications before combining. Based on 6 of 16 ingredients. Check your meds →
Dietary supplement

Extreme Instant EAA Blackberry Flavour Ingredients & Drug Interactions

by Body Attack

Extreme Instant EAA Blackberry 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 Blackberry 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 Blackberry Flavour is a dietary supplement by Body Attack with 16 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 Blackberry Flavour by Body Attack

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Extreme Instant EAA Blackberry 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 13 of its 13 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Extreme Instant EAA Blackberry Flavour contains 13 ingredients, including essential amino acids (the building blocks your body uses to make and repair tissue) and vitamin B6. The essential amino acids are L-methionine, L-phenylalanine, L-isoleucine, L-valine, L-lysine, L-threonine, L-tryptophan, and L-leucine.

The product also includes fat, saturated fatty acids, salt, and inactive ingredients like maltodextrin, citric acid, flavoring, sucralose, and acesulfame potassium (sweeteners), and silicon dioxide.

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 muscle and training support.
  • We looked for evidence on: Athletic performance, Muscle strength, Exercise recovery, Protein synthesis.
  • 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 evidence we hold rates vitamin B6 as effective for sideroblastic anemia and vitamin B6 deficiency, and likely effective for elevated homocysteine (a risk factor for heart disease). It's rated possibly effective for pregnancy-related nausea and vomiting, though safety requires a clinician's guidance.

For the amino acids in this product—L-phenylalanine, L-lysine, L-tryptophan, and threonine—the evidence we hold shows mostly insufficient or ineffective ratings for the conditions studied. L-lysine is rated possibly effective for cold sores.

We hold no effectiveness data on L-methionine, L-isoleucine, or L-valine in our files.

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.

Vitamin B6 is well tolerated in doses under 100 mg daily, though high doses over time can harm nerves (a condition called sensory neuropathy). The most common side effects at normal doses are abdominal pain, headache, heartburn, nausea, and loss of appetite.

L-phenylalanine is generally well tolerated at typical doses but should be avoided during pregnancy and breastfeeding because safety hasn't been established. Common side effects include anxiety, constipation, headache, heartburn, insomnia, and nausea.

L-tryptophan is generally well tolerated but has a history tied to a contaminated-product safety issue in the late 1980s (almost all cases traced to one Japanese manufacturer); it should be avoided in pregnancy and breastfeeding. Common side effects are drowsiness, headache, nausea, and stomach pain.

L-lysine is generally well tolerated, though high amounts may cause stomach upset; supplement safety during pregnancy and breastfeeding isn't well studied. L-methionine and L-threonine are well tolerated at food amounts; supplement safety in pregnancy and breastfeeding is not well studied.

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.

Check with your pharmacist if you take levodopa (Parkinson's medication), CNS depressants like sedatives or sleep aids, serotonin-boosting drugs (certain antidepressants), seizure medications like phenobarbital or phenytoin, blood-pressure medications, the heart drug amiodarone, muscle relaxants like baclofen, or older antidepressants called MAOIs. For the other ingredients in this product, we hold no interaction data, so we can't assess them.

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 vitamin supplement designed to support muscle protein. If you take levodopa for Parkinson's, blood-pressure medication, seizure medication, sedating drugs, serotonin-boosting antidepressants, or a muscle relaxant, check with your pharmacist before starting—several of the amino acids and vitamin B6 in here interact with those drug classes.

Pregnant or breastfeeding? Talk to your doctor first, particularly about L-phenylalanine and L-tryptophan.

Your pharmacist can help you figure out whether this product and your current medications are a good match.

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

Assessment coverage: 6 of 13 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 21, 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 Blackberry Flavour, straight from the product label.

Brand Body Attack
Barcode (UPC) 4250350549032
Net contents 500 Gram(s)
Market status On market
Date entered into DSLD May 21, 2025
DSLD ID 329555
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 Blackberry 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
4250350549032
IngredientAmount% DV
Vitamin B60.5 mg35%
L-Methionine900 mg--
Protein9.5 Gram(s)--
Energy51 Kcal(s)--
Fat0.1 Gram(s)--
Carbohydrate1.5 Gram(s)--
Total Essential Amino Acids9461 mg--
L-Phenylalanine1.005 mg--
Saturated Fatty Acids0.1 Gram(s)--
Sugar0.2 Gram(s)--
Salt0.01 Gram(s)--
L-Isoleucine1229 mg--
L-Valine1229 mg--
L-Lysine1.5 mg--
L-Threonine900 mg--
L-Tryptophan240 mg--
L-Leucine2458 mg--

Other ingredients: L-Leucine, Citric Acid, L-Lysine Hydrochloride, Maltodextrin, L-Phenylalanine, L-Methionine, L-Threonine, Flavoring, L-Tryptophan, Anthocyanin, Acesulfame Potassium, Sucralose, Silicon Dioxide, Coconut, Palm, 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 no 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 children.

FDA Statement of Identity

Food supplement with sweeteners.

Formula

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

High dose premium EAA with vitamin B6

BCAA: branched chain amino acids [L-Isoleucine, L-Isoleucine, L-Valine] Essential amino acids

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 V Vegan

Formulation

V Vegan

Sugar free Lactose free

General

Content 35 servings

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

See for yourself

Extreme Instant EAA Blackberry Flavour by Body Attack label

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

Extreme Instant EAA Blackberry 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 Blackberry Flavour by Body Attack

These are the 16 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

L-Methionine

No known
interactions
900 mg per serving

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a norma...

L-Methionine monograph & interactions

Protein

9.5 Gram(s) per serving

Energy

51 Kcal(s) per serving

Fat

0.1 Gram(s) per serving

Carbohydrate

1.5 Gram(s) per serving
  • › Sugar

Total Essential Amino Acids

9461 mg per serving

L-Phenylalanine

Interacts with
16 drugs
1.005 mg per serving

Phenylalanine is an essential amino acid the body uses to make brain chemicals like dopamine and norepinephrine. Some people take it for mood, vitilig...

L-Phenylalanine monograph & interactions

Saturated Fatty Acids

0.1 Gram(s) per serving

Salt

0.01 Gram(s) per serving

L-Isoleucine

1229 mg per serving

L-Valine

1229 mg per serving

L-Lysine

Interacts with
1 drug
1.5 mg per serving

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 t...

L-Lysine monograph & interactions

L-Threonine

Interacts with
3 drugs
900 mg per serving

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 norma...

L-Threonine monograph & interactions

L-Tryptophan

Interacts with
394 drugs
240 mg per serving

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...

L-Tryptophan monograph & interactions

L-Leucine

2458 mg per serving

Other (inactive) ingredients: L-Leucine, Citric Acid, L-Lysine Hydrochloride, Maltodextrin, L-Phenylalanine, L-Methionine, L-Threonine, Flavoring, L-Tryptophan, Anthocyanin, Acesulfame Potassium, Sucralose, Silicon Dioxide, Coconut, Palm, Lecithin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Extreme Instant EAA Blackberry Flavour by Body Attack Drug Interactions

Want to check YOUR meds against Extreme Instant EAA Blackberry 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 Blackberry Flavour interact with 579 drugs. Click any drug to see the details.

5 of the 16 ingredients in Extreme Instant EAA Blackberry 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 Blackberry 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 Blackberry 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 Blackberry Flavour by Body Attack: Common Questions

Does Extreme Instant EAA Blackberry Flavour by Body Attack interact with any medications?
Yes. Based on its ingredients, Extreme Instant EAA Blackberry 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 Blackberry Flavour contains 16 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.
What are these amino acids actually for?
Essential amino acids are the raw materials your body needs to build and repair muscle tissue, make enzymes, and support other functions. This product combines eight of them—leucine, isoleucine, valine, phenylalanine, methionine, threonine, tryptophan, and lysine—plus vitamin B6. You can get amino acids from food (especially protein), but this supplement delivers them as a powder to mix into drinks.
Can I take this if I'm pregnant?
L-phenylalanine and L-tryptophan should be avoided during pregnancy because safety hasn't been established. The facts don't have complete safety information on the other amino acids during pregnancy either. Talk with your doctor or pharmacist before using this—they can weigh the risks and benefits for your situation.
Can I take this while breastfeeding?
The data we hold advises against L-phenylalanine and L-tryptophan while breastfeeding. Safety of the other amino acids in breast milk is not well studied. Check with your pharmacist or doctor first.
What side effects might I notice?
Common ones are mild—nausea, headache, heartburn, diarrhea, constipation, and stomach pain. L-tryptophan can make you drowsy. If you take high doses of vitamin B6 over time, there's a risk of nerve damage (sensory neuropathy). Serious side effects are rare, but if you notice unusual symptoms, stop and talk to your pharmacist.
Is this safe for someone with PKU?
No. This product contains L-phenylalanine, and phenylketonuria (PKU) is a condition where your body can't properly process phenylalanine. If you have PKU, avoid this supplement and tell your pharmacist about any new products.
Does this actually help with muscle growth?
The evidence we hold on the amino acids in this product doesn't establish that they build muscle or boost athletic performance. Amino acids are important building blocks, but we can't claim this product will improve muscle based on the data we have on file.

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

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

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Ask a pharmacist

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 Blackberry Flavour label
Go deeper

The Full Monographs Behind Extreme Instant EAA Blackberry 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 Blackberry 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
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Methionine 12 references
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  8. Ward, M., McNulty, H., McPartlin, J., Strain, J. J., Weir, D. G., and Scott, J. M. Effect of supplemental methionine on plasma homocysteine concentrations in healthy men: a preliminary study. Int.J.Vitam.Nutr.Res. 2001;71(1):82-86. PubMed
  9. Yaghmai, R., Kashani, A. H., Geraghty, M. T., Okoh, J., Pomper, M., Tangerman, A., Wagner, C., Stabler, S. P., Allen, R. H., Mudd, S. H., and Braverman, N. Progressive cerebral edema associated with high methionine levels and betaine therapy in a patient
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  12. Khairan P, Sobue T, Eshak ES, et al. Association of B Vitamins and Methionine Intake with the Risk of Gastric Cancer: The Japan Public Health Center-based Prospective Study. Cancer Prev Res (Phila) 2022;15(2):101-110. PubMed

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Phenylalanine 23 references
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  17. Fischer, E., Heller, B., Nachon, M., and Spatz, H. Therapy of depression by phenylalanine. Preliminary note. Arzneimittelforschung. 1975;25(1):132.
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  22. Mann, J., Peselow, E. D., Snyderman, S., and Gershon, S. D-phenylalanine in endogenous depression. Am.J.Psychiatry 1980;137(12):1611-1612. PubMed
  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
  2. McCune MA, Perry HO, Muller SA, O'Fallon WM. Treatment of recurrent herpes simplex infections with L-lysine monohydrochloride. Cutis 1984;34:366-73.
  3. DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol 1984;120:48-51. DOI
  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.
  5. Griffith RS, Walsh DE, Myrmel KH, et al. Success of L-lysine therapy in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Dermatologica 1987;175:183-90. DOI
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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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  4. Roufs JB. L-threonine as a symptomatic treatment for amyotrophic lateral sclerosis (ALS). Med Hypotheses 1991;34:20-3. PubMed

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L-tryptophan 18 references
  1. Messiha FS. Fluoxetine: adverse effects and drug-drug interactions. J Toxicol Clin Toxicol 1993;31:603-30. PubMed
  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.
  5. Sullivan EA, Kamb ML, Jones JL, et al. The natural history of eosinophilia-myalgia syndrome in a tryptophan-exposed cohort in South Carolina. Arch Intern Med 1996;156:973-9. DOI
  6. Philen RM, Hill RH, Flanders WD, et al. Tryptophan contaminants associated with eosinophilia-myalgia syndrome. Am J Epidemiol 1993;138:154-9. PubMed
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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

See these in context on the L-tryptophan monograph →

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