Major interaction on record — check this product against your medications before combining. Based on 5 of 14 ingredients. Check your meds →
Dietary supplement

Clear Iso Whey Blackberry Ingredients & Drug Interactions

by Body Attack

Clear Iso Whey Blackberry label
See full label image
Powder Category: Amino Acid/protein
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Clear Iso Whey Blackberry 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

Clear Iso Whey Blackberry is a dietary supplement by Body Attack with 14 active ingredients. Its ingredients are commonly taken for depression and mood, skin condition vitiligo, pain conditions.Based on those ingredients, 407 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Tryptophan, L-Phenylalanine, L-Threonine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Clear Iso Whey Blackberry by Body Attack

Ask about any prescription or over-the-counter medication and we check it for interactions with Clear Iso Whey Blackberry 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 Clear Iso Whey Blackberry 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

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 9 active ingredients.
  • “Fat” is listed as a grouped ingredient — the label gives one combined amount (0.40 Gram(s)) without saying how much of each component you get.
  • “Essential Amino Acids” is listed as a grouped ingredient — the label gives one combined amount (37.70 Gram(s)) without saying how much of each component you get.

Clear Iso Whey Blackberry is a whey protein powder with 10 active amino acids: L-phenylalanine, L-valine, L-threonine, L-tryptophan, L-isoleucine, L-leucine, L-methionine, L-lysine, and a blend called Essential Amino Acids. These amino acids are the building blocks your body uses for muscle repair and protein synthesis.

The inactive ingredients include whey protein isolate, flavoring, citric acid, sweeteners, and other excipients like silicon dioxide and diglycerides.

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: protein drink for muscle and nutrition.
  • We looked for evidence on: Athletic performance, Muscle strength, Child growth, Wound healing, Muscle recovery, Sports nutrition — and 1 related terms.
  • The closest evidence on file: Methionine is rated "Insufficient Reliable Evidence To Rate" for Wound healing (Natural Medicines).
  • Also on file: Lysine is rated "Insufficient Reliable Evidence To Rate" for Athletic performance, Muscle strength, Child growth.
  • Also on file: L-tryptophan is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.

The data we hold on these amino acids focuses mainly on specific medical conditions, not muscle protein synthesis or athletic recovery. L-phenylalanine shows possibly ineffective evidence for ADHD and possibly effective for vitiligo.

L-lysine is possibly effective for cold sores (herpes labialis). L-methionine is possibly effective for neural tube birth defects in pregnancy.

L-tryptophan is possibly ineffective for depression. L-threonine shows insufficient evidence for multiple sclerosis and spasticity.

Overall, evidence for this product's use as a muscle-building or recovery supplement is not established in the data we hold.

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

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-phenylalanine and L-tryptophan are generally well tolerated at typical doses in food, but common side effects include anxiety, insomnia, nausea, headache, constipation, and heartburn. L-tryptophan can cause drowsiness and lightheadedness.

L-threonine may cause headache and minor GI upset like diarrhea. L-lysine is generally well tolerated but may cause stomach upset and diarrhea at high doses.

L-methionine is well tolerated in food amounts but high-dose supplements may cause dizziness, drowsiness, and vomiting. Important: avoid L-phenylalanine, L-tryptophan, and L-threonine in supplement doses during pregnancy and breastfeeding due to insufficient safety data; L-methionine and L-lysine from supplements in pregnancy and breastfeeding also lack proven safety.

Do not use if you have phenylketonuria (PKU).

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

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?
  • 4 of the 5 matched ingredients can interact with medications — Lysine, L-tryptophan, Phenylalanine, Threonine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 407 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, check if you use levodopa (Parkinson disease), CNS depressants like benzodiazepines or opioids, serotonergic drugs such as SSRIs or SNRIs, monoamine oxidase inhibitors (older antidepressants), baclofen (muscle relaxant), NMDA antagonists, or 5-HT4 agonists. These interactions range from Major to Minor severity.

Use the medication checker on this page to confirm your specific drugs.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

This whey protein powder is marketed as a muscle-building supplement, but we hold limited evidence of its effectiveness for athletic recovery. If you take any prescription medications — especially Parkinson medications, antidepressants, sedatives, blood pressure drugs, or muscle relaxants — check them against the medication search tool below before starting.

Talk to your pharmacist or doctor about whether this product is right for you, especially if you're pregnant, breastfeeding, or have PKU.

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

Assessment coverage: 5 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 22, 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 Clear Iso Whey Blackberry, straight from the product label.

Brand Body Attack
Barcode (UPC) 4250350546741
Net contents 900 Gram(s)
Market status On market
Date entered into DSLD Aug 22, 2025
DSLD ID 337752
Product type Amino Acid/protein
Supplement form Powder
Dietary claims / uses Nutrient, All Other
Intended target group(s) Adult (18 - 50 Years), 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 Clear Iso Whey Blackberry 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:
30 Gram(s)
Maximum serving Sizes:
30 Gram(s)
Servings per container
30
UPC/BARCODE
4250350546741
IngredientAmount% DV
Sugar0 Gram(s), 0 Gram(s)--
L-Phenylalanine0 NP, 0 NP--
L-Valine0 NP, 0 NP--
L-Threonine0 NP, 0 NP--
L-Tryptophan0 NP, 0 NP--
Energy444 kJ--
Saturated Fat0.4 Gram(s), 0.1 Gram(s)--
Protein81.7 Gram(s), 24.5 Gram(s)--
Salt0.08 Gram(s), 0.02 Gram(s)--
L-Isoleucine0 NP, 0 NP--
Fat0.4 Gram(s), 0.1 Gram(s)--
Energy1482 kJ--
Carbohydrates3.5 Gram(s), 1 Gram(s)--
Essential Amino Acids37.7 Gram(s), 11.3 Gram(s)--
L-Leucine0 NP, 0 NP--
L-Methionine0 NP, 0 NP--
L-Lysine0 NP, 0 NP--

Other ingredients: Whey Protein Isolate, Flavoring, Citric Acid, Sucralose, Acesulfame Potassium, Anthocyanins, Monoglycerides, Diglycerides, Silicon Dioxide

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: 30g of powder (3 scoops) into 500 mL of water. Let it set for 30-60 seconds. Recommended dosage: Mix 30g powder (3 scoops) with 500 mL water in a shaker and let it set for 30-60 seconds. Directions: On training days, drink about 30 minutes before or after an intensive workout. On non-training days, drink in the morning or evening.

We recommend a varied, balanced diet and a healthy lifestyle.

Formula

Protein blend as a protein concentrate with sweeteners for the preparation of a protein drink. Flavouring: Blackberry.

Whey protein isolate powder Protein 24.5 g EAA 11300 mg Per 30 g in 500 mL water CFM Whey Isolate

Storage

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

Seals/Symbols

Made in Germany

Formulation

Fat free Sugar free Lactose free

Clear refreshing protein drink

GMO free

General Statements

Amino acid profile: L-Alanine 5,29 g L-Arginine 1,83 g L-Aspartic Acid 10,56 g L-Cysteine 2,15 g L-Glutamic Acid 17,69 g Glycine 1,42 g L-Histidine 1,52 g L-Isoleucine 6,43 g L-Leucine 10,64 g L-Lysine 9,54 g L-Methionine 2,15 g L-Phenylalanine 2,86 g L-Proline 6,17 g L-Serine 4,56 g L-Threonine 7,07 g L-Tryptophan 1,72 g L-Tyrosine 2,64 g L-Valine 5,72 g EAA (Essential amino acids (L-Isoleucine, L-Leucine, L-Lysine, L-Methionine, L-Phenylalanine, L-Threonine, L-Tryptophan, L-Valine)) The amino acid profile refers to the proteins contained in the product. CFM = Cross Flow Microfiltration

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

See for yourself

Clear Iso Whey Blackberry by Body Attack label

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

Clear Iso Whey Blackberry 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 Clear Iso Whey Blackberry by Body Attack

These are the 14 active ingredients this product is made of. Select any to open its full monograph.

Serving size30 Gram(s) Dosage formPowder Servings per container30 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.

Energy

444 kJ per serving

Protein

81.7 Gram(s) per serving

Salt

0.08 Gram(s) per serving

Fat

0.4 Gram(s) per serving

Energy

1482 kJ per serving

Carbohydrates

3.5 Gram(s) per serving
  • › Sugar

Essential Amino Acids

37.7 Gram(s) per serving

Other (inactive) ingredients: Whey Protein Isolate, Flavoring, Citric Acid, Sucralose, Acesulfame Potassium, Anthocyanins, Monoglycerides, Diglycerides, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Clear Iso Whey Blackberry by Body Attack Drug Interactions

Want to check YOUR meds against Clear Iso Whey Blackberry?

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
407Drugs
256 Major 151 Moderate

Ingredients driving the most interactions

L-Tryptophan 394
L-Phenylalanine 16
L-Threonine 3
L-Lysine 1

Individual Drug Interactions

The ingredients in Clear Iso Whey Blackberry interact with 407 drugs. Click any drug to see the details.

4 of the 14 ingredients in Clear Iso Whey Blackberry interact with drugs. Each result below shows which ingredient is responsible. L-Tryptophan L-Phenylalanine L-Threonine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Clear Iso Whey Blackberry 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

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 Clear Iso Whey Blackberry, 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

Clear Iso Whey Blackberry by Body Attack: Common Questions

Does Clear Iso Whey Blackberry by Body Attack interact with any medications?
Yes. Based on its ingredients, Clear Iso Whey Blackberry has a known interaction with 407 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?
Clear Iso Whey Blackberry contains 14 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?
No, not safely. The amino acids L-phenylalanine, L-tryptophan, and L-threonine should be avoided in supplement doses during pregnancy and breastfeeding because safety has not been established. L-methionine and L-lysine from supplements also lack proven safety during these times. Talk with your doctor or pharmacist first.
Is this product safe if I have PKU?
No. Do not use this product if you have phenylketonuria (PKU), because it contains L-phenylalanine, which people with PKU cannot safely metabolize.
What are the most common side effects?
The amino acids in this powder may cause anxiety, insomnia, nausea, headache, constipation, heartburn, and drowsiness. L-tryptophan in particular can cause fatigue and lightheadedness. Most people tolerate these ingredients at typical doses, but individual sensitivity varies.
Does this supplement actually help with muscle building?
The data we hold on these individual amino acids focuses on specific medical conditions, not athletic performance or muscle recovery. Evidence for those uses is not established in our records. Talk to your coach or doctor about whether this product fits your fitness goals.
Why do I need to check my medications before taking this?
Because several amino acids in this powder — especially L-phenylalanine, L-tryptophan, and L-threonine — interact with common prescription drugs. These interactions can reduce how well your medications work or increase side effects. The checker below will tell you if any of your drugs are affected.

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

Not sure if Clear Iso Whey Blackberry is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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.

Clear Iso Whey Blackberry label
Go deeper

The Full Monographs Behind Clear Iso Whey Blackberry’s Ingredients

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

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

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 → 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

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 →
Sources

Sources & How We Checked

Clear Iso Whey Blackberry'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 64 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.

Phenylalanine 23 references
  1. Rouse B, Azen C, Koch R, et al. Maternal phenylketonuria collaborative Study (MPKUCS) offspring: facial anomalies, malformations, and early neurological sequelae. Am J Med Genet 1997;69:89-95. DOI
  2. Sturtevant FM. Use of aspartame in pregnancy. Int J Fertil 1985;30:85-7.
  3. Silkaitis RP, Mosnaim AD. Pathways linking L-phenylalanine and 2-phenylethylamine with p-tyramine in rabbit brain. Brain Res 1976;114:105-15.
  4. Lehmann WD, Theobald N, Fischer R, Heinrich HC. Stereospecificity of phenylalanine plasma kinetics and hydroxylation in man following oral application of a stable isotope-labelled pseudo-racemic mixture of L- and D-phenylalanine. Clin Chim Acta 1983;128 PubMed
  5. Mosnik DM, Spring B, Rogers K, Baruah S. Tardive dyskinesia exacerbated after ingestion of phenylalanine by schizophrenic patients. Neuropsychopharmacology 1997;16:136-46. PubMed
  6. Siddiqui AH, Stolk LM, Bhaggoe R, et al. L-phenylalanine and UVA irradiation in the treatment of vitiligo. Dermatology 1994;88:215-8. PubMed
  7. Birkmayer W, Riederer P, Linauer W, Knoll J. L-deprenyl plus L-phenylalanine in the treatment of depression. J Neural Transm 1984;59:81-7. PubMed
  8. Nutt JG, Woodward WR, Hammerstad JP, et al. The "on-off" phenomenon in Parkinson's disease. Relation to levodopa absorption and transport. N Engl J Med 1984;310:483-8. PubMed
  9. Baruzzi A, Contin M, Riva R, et al. Influence of meal ingestion time on pharmacokinetics of orally administered levodopa in parkinsonian patients. Clin Neuropharmacol 1987;10:527-37. PubMed
  10. Juncos JL, Fabbrini G, Mouradian MM, et al. Dietary influences on the antiparkinsonian response to levodopa. Arch Neurol 1987;44:1003-5. PubMed
  11. Eriksson T, Granerus AK, Linde A, et al. "On-off" phenomenon in Parkinson's disease: relationship between dopa and other large neutral amino acids in plasma. Neurology 1988;38:1245-8. PubMed
  12. Baker GB, Bornstein RA, Rouget AC, et al. Phenylethylaminergic mechanisms in attention-deficit disorder. Biol Psychiatry 1991;29:15-22.. PubMed
  13. Wood DR, Reimherr FW, Wender PH. Treatment of attention deficit disorder with DL-phenylalanine. Psychiatry Res 1985;16:21-6.. PubMed
  14. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington, DC: National Academy Press, 2002. Available at: http://www.n
  15. Cederbaum S. Phenylketonuria: an update. Curr Opin Pediatr 2002;14:702-6. PubMed
  16. Cejudo-Ferragud, E., Nacher, A., Polache, A., Cercos-Fortea, T., Merino, M., and Casabo, V. G. Evidence of competitive inhibition for the intestinal absorption of baclofen by phenylalanine. Int J of Pharm (Amsterdam) 1996;132:63-69. DOI
  17. Fischer, E., Heller, B., Nachon, M., and Spatz, H. Therapy of depression by phenylalanine. Preliminary note. Arzneimittelforschung. 1975;25(1):132.
  18. Beckmann, H., Strauss, M. A., and Ludolph, E. Dl-phenylalanine in depressed patients: an open study. J.Neural Transm. 1977;41(2-3):123-134. PubMed
  19. Sabelli, H. C., Fawcett, J., Gusovsky, F., Javaid, J. I., Wynn, P., Edwards, J., Jeffriess, H., and Kravitz, H. Clinical studies on the phenylethylamine hypothesis of affective disorder: urine and blood phenylacetic acid and phenylalanine dietary supplem
  20. Cotzias, G. C., Van Woert, M. H., and Schiffer, L. M. Aromatic amino acids and modification of parkinsonism. N Engl.J Med 2-16-1967;276(7):374-379. PubMed
  21. Kravitz, H. M., Sabelli, H. C., and Fawcett, J. Dietary supplements of phenylalanine and other amino acid precursors of brain neuroamines in the treatment of depressive disorders. J Am Osteopath.Assoc 1984;84(1 Suppl):119-123. DOI
  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

See these in context on the Phenylalanine monograph →

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
  2. Lee A, Patterson V. A double blind study of L-threonine in patients with spinal spasticity. Acta Neurol Scand 1993;88:334-8. PubMed
  3. Blin O, Pouget J, Aubrespy G, et al. A double-blind placebo controlled trial of L-threonine in amyotrophic lateral sclerosis. J Neurol 1992;239:79-81.
  4. Roufs JB. L-threonine as a symptomatic treatment for amyotrophic lateral sclerosis (ALS). Med Hypotheses 1991;34:20-3. PubMed

See these in context on the Threonine monograph →

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
  3. Lieberman HR, Corkin S, Spring BJ. The effects of dietary neurotransmitter precursors on human behavior. Am J Clin Nutr 1985;42:366-70. PubMed
  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
  7. Bohme A, Wolter M, Hoelzer D. L-tryptophan-related eosinophilia-myalgia syndrome possibly associated with a chronic B-lymphocytic leukemia. Ann Hematol 1998;77:235-8. PubMed
  8. Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
  9. Priori R, Conti F, Luan FL, et al. Chronic fatigue: a peculiar evolution of eosinophilia myalgia syndrome following treatment with L-tryptophan in four Italian adolescents. Eur J Pediatr 1994;153:344-6..
  10. Klein R, Berg PA. A comparative study on antibodies to nucleoli and 5-hydroxytryptamine in patients with fibromyalgia syndrome and tryptophan-induced eosinophilia-myalgia syndrome. Clin Investig 1994;72:541-9.. PubMed
  11. Simat TJ, Kleeberg KK, Muller B, Sierts A. Synthesis, formation, and occurrence of contaminants in biotechnologically manufactured L-tryptophan. Adv Exp Med Biol 1999;467:469-80.. PubMed
  12. Shaw K, Turner J, Del Mar C. Tryptophan and 5-hydroxytryptophan for depression. Cochrane Database Syst Rev 2002;(1):CD003198. PubMed
  13. Kilbourne EM, Philen RM, Kamb ML, Falk H. Tryptophan produced by Showa Denko and epidemic eosinophilia-myalgia syndrome. J Rheumatol Suppl 1996;46:81-8.
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  16. Mayeno AN, Gleich GJ. The eosinophilia-myalgia syndrome: lessons from Germany. Mayo Clin Proc 1994;69:702-4. PubMed
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See these in context on the L-tryptophan monograph →

Methionine 12 references
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  6. McAuley, D. F., Hanratty, C. G., McGurk, C., Nugent, A. G., and Johnston, G. D. Effect of methionine supplementation on endothelial function, plasma homocysteine, and lipid peroxidation. J.Toxicol.Clin.Toxicol. 1999;37(4):435-440. PubMed
  7. Hanratty, C. G., McGrath, L. T., McAuley, D. F., Young, I. S., and Johnston, G. D. The effects of oral methionine and homocysteine on endothelial function. Heart 2001;85(3):326-330. PubMed
  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

See these in context on the Methionine monograph →

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
  6. Lo JC, Chertow GM, Rennke H, Seifter JL. Fanconi's syndrome and tubulointerstitial nephritis in association with L-lysine ingestion. Am J Kidney Dis 1996;28:614-7. PubMed
  7. Smriga M, Torii K. L-Lysine acts like a partial serotonin receptor 4 antagonist and inhibits serotonin-mediated intestinal pathologies and anxiety in rats. Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15370-5.

See these in context on the Lysine monograph →

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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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