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 Ice Tea Lemon Flavour Ingredients & Drug Interactions

by Body Attack

Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon 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 Ice Tea Lemon 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 Ice Tea Lemon Flavour by Body Attack

Ask about any prescription or over-the-counter medication and we check it for interactions with Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon 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 Ice Tea is a powder with 13 ingredients, including active amino acids. The essential amino acids here — L-phenylalanine, L-isoleucine, L-valine, L-leucine, L-methionine, L-threonine, L-tryptophan, and L-lysine — are the building blocks your body uses for muscle recovery and protein synthesis.

Vitamin B6 is a B vitamin involved in amino acid metabolism and nerve function. The rest are inactive ingredients: fillers and flavor agents like citric acid, maltodextrin, various flavoring compounds, sweeteners (acesulfame potassium, sucralose), coconut oil, palm oil, silicon dioxide (an anti-caking agent), and caramel coloring.

Does it work?

Insufficient 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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Essential amino acids for athletic performance and recovery.
  • We looked for evidence on: Athletic performance, Muscle strength, Child growth, muscle recovery, protein synthesis, training support.
  • 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, Child growth.
  • Also on file: L-tryptophan is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.

The only ingredient in this product with established effectiveness data is vitamin B6. It's effective for sideroblastic anemia and vitamin B6 deficiency, and likely effective for high homocysteine levels.

It's possibly effective for pregnancy-related nausea and vomiting. The amino acids here — L-phenylalanine, L-tryptophan, L-lysine, and L-threonine — have mixed or insufficient evidence.

L-phenylalanine is possibly ineffective for ADHD. L-lysine is possibly effective for cold sores but has insufficient evidence for growth and wound healing.

L-tryptophan is possibly ineffective for depression and has insufficient evidence for anxiety and other uses. L-threonine is possibly ineffective for ALS and has insufficient evidence for multiple sclerosis and spasticity.

L-methionine, L-isoleucine, L-valine, and L-leucine have no effectiveness ratings on file.

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 at doses under 100 mg daily, but high doses over time can damage nerves (sensory neuropathy), especially above 1,000 mg daily or cumulative doses of 1,000 grams or more. Common side effects at any dose include headache, nausea, abdominal pain, vomiting, and loss of appetite.

L-phenylalanine is generally well tolerated at typical doses and commonly causes anxiety, constipation, headache, heartburn, insomnia, and nausea. L-tryptophan is generally well tolerated at normal doses but can cause drowsiness, nausea, diarrhea, headache, and other GI upset; a contaminated batch in 1989 caused a rare neurological condition called eosinophilia-myalgia syndrome (nearly all cases were traced to one Japanese manufacturer and are unlikely to recur).

L-lysine is generally well tolerated and most commonly causes abdominal pain, diarrhea, and heartburn. L-methionine can cause dizziness, drowsiness, low blood pressure, and vomiting.

L-threonine may cause headache and minor GI upset including diarrhea. Pregnancy and breastfeeding safety data are limited for most amino acids in this product — L-methionine is rated likely safe during pregnancy and lactation, but L-phenylalanine and L-tryptophan should be avoided in pregnancy and breastfeeding due to lack of safety studies.

For L-lysine and L-threonine, supplement doses have not been well studied in pregnancy or breastfeeding, so talk with your doctor first.

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 levodopa (Parkinson's disease), CNS depressants such as benzodiazepines, opioids, and sleep aids, serotonergic drugs including SSRIs and SNRIs (common antidepressants), antihypertensive medications, amiodarone (heart rhythm medication), phenobarbital and phenytoin (seizure drugs), and NMDA antagonists like memantine. No interactions are documented in our data for fat, total essential amino acids, saturated fatty acids, salt, L-isoleucine, L-valine, or L-leucine.

Check your own medication Run your meds through the checker above

The bottom line

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

This is an essential amino acid formula with vitamin B6 meant for muscle recovery. If you take levodopa, sedatives, serotonergic antidepressants, antihypertensive drugs, antiarrhythmic drugs, seizure medications, or NMDA antagonists, check your specific medications with the tool on this page before starting.

Pregnant or breastfeeding women should discuss it with their doctor or pharmacist first. Talk to us or your pharmacist if you're unsure.

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 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 Ice Tea Lemon Flavour, straight from the product label.

Brand Body Attack
Barcode (UPC) 4250350537336
Net contents 500 Gram(s)
Market status On market
Date entered into DSLD Jul 24, 2025
DSLD ID 334229
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 Ice Tea Lemon 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
4250350537336
IngredientAmount% DV
Vitamin B60.5 mg35%
L-Methionine900 mg--
Protein9.5 Gram(s)--
Energy52 Kcal(s)--
Fat0.1 Gram(s)--
Carbohydrate1.6 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, Acesulfame Potassium, Sucralose, Coconut Oil, Palm Oil, Sulphite Ammonia Caramel, Silicon Dioxide, 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: Ice Tea Lemon.

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 Ice Tea Lemon Flavour by Body Attack label

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

Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon 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

52 Kcal(s) per serving

Fat

0.1 Gram(s) per serving

Carbohydrate

1.6 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, Acesulfame Potassium, Sucralose, Coconut Oil, Palm Oil, Sulphite Ammonia Caramel, Silicon Dioxide, Lecithin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Extreme Instant EAA Ice Tea Lemon Flavour by Body Attack Drug Interactions

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

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

Does Extreme Instant EAA Ice Tea Lemon Flavour by Body Attack interact with any medications?
Yes. Based on its ingredients, Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon 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.
Can I take this if I'm pregnant?
L-methionine in this product is rated likely safe during pregnancy, but L-phenylalanine and L-tryptophan should be avoided because their safety hasn't been established. For the other amino acids and vitamin B6, safety data during pregnancy is limited. Talk with your doctor or pharmacist before taking it — they can weigh the risks and benefits for your situation.
What are the common side effects?
The amino acids and vitamin B6 in typical doses are generally well tolerated. Most common side effects reported include headache, nausea, abdominal pain, diarrhea, heartburn, constipation, and drowsiness. High doses of vitamin B6 over time can cause nerve damage.
Is this safe if I'm breastfeeding?
L-methionine is rated likely safe while breastfeeding, but L-phenylalanine and L-tryptophan should be avoided due to lack of safety data. The other amino acids and vitamin B6 have not been well studied during breastfeeding, so check with your doctor or pharmacist first.
What is L-tryptophan, and why is it here?
L-tryptophan is an essential amino acid your body uses to make serotonin and other molecules. It's included in this EAA blend to support muscle protein synthesis and recovery. However, it can make you drowsy and shouldn't be combined with sedating medications.
Does this work for muscle recovery?
The amino acids in this product are essential building blocks for muscle repair and growth, but the product facts we have don't include effectiveness studies specifically on muscle recovery or athletic performance. Most EAA products are used for that purpose, but we can't claim it based on the data on file.
What if I have phenylketonuria (PKU)?
L-phenylalanine is an amino acid that people with PKU must avoid because their bodies can't process it properly. This product contains L-phenylalanine, so it is not safe for you. Talk to your doctor or pharmacist about suitable alternatives.

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

Not sure if Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon Flavour label
Go deeper

The Full Monographs Behind Extreme Instant EAA Ice Tea Lemon 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 Ice Tea Lemon 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.
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Methionine 12 references
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Phenylalanine 23 references
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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.
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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

See these in context on the L-tryptophan monograph →

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