L-Tryptophan 500 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Tryptophan 500 mg 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
L-Tryptophan 500 mg is a dietary supplement by The Vitamin Shoppe with 1 active ingredient. Its ingredients are commonly taken for sleep problems, low mood and depression, anxiety.Based on those ingredients, 394 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Tryptophan. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against L-Tryptophan 500 mg by The Vitamin Shoppe
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tryptophan 500 mg by The Vitamin Shoppe — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of L-Tryptophan 500 mg by The Vitamin Shoppe
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.
What’s inside
Full disclosure
This product contains one active ingredient: L-Tryptophan 500 mg per capsule. L-Tryptophan is an amino acid your body uses to make serotonin, a chemical messenger tied to mood, sleep, and relaxation.
The capsule itself and the inactive ingredients — vegetable capsule, microcrystalline cellulose, magnesium stearate, and silicon dioxide — are fillers and binders.
Does it work?
Not established
The evidence for L-Tryptophan's effectiveness is limited. For depression, it's rated possibly ineffective.
For anxiety, athletic performance, teeth grinding (bruxism), and premenstrual dysphoric disorder (PMDD), there isn't enough reliable evidence to say whether it works. This doesn't mean it doesn't work for you — just that solid clinical proof is lacking in the data we hold.
How safe is it?
Well-documented data
L-Tryptophan is generally well tolerated when taken by mouth, but you may experience mild side effects: belching, diarrhea, drowsiness, dry mouth, gas, headache, heartburn, lightheadedness, nausea, stomach pain, blurred vision, or vomiting. Rare serious effects include eosinophilia-myalgia syndrome (EMS), a neurological disorder; most cases in the late 1980s were traced to contaminated product from a single Japanese manufacturer and led to an FDA recall and import restrictions.
For pregnancy, the safety data is mixed — one rating says possibly unsafe, another says likely safe; the contradiction means you should talk with your doctor or midwife before using it. For breastfeeding, safety is not established, so avoid it unless your doctor advises otherwise.
Meds to double-check
Major interaction found
Before taking this product, double-check with your doctor or pharmacist if you use any central nervous system depressants — sleep aids, anti-anxiety medications, opioid painkillers, or alcohol — because L-Tryptophan could dangerously amplify sedation. Also verify your use of any serotonergic drugs, including antidepressants, certain migraine treatments, or any medication that raises serotonin levels.
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.
L-Tryptophan may appeal to you if you're interested in a natural approach to mood or sleep, but the evidence for it working is weak to absent. The real caution here is drug interactions — especially if you take sedating medications or serotonin-based antidepressants.
Talk with your doctor or pharmacist about your specific situation before starting, particularly if you're pregnant, nursing, or taking any prescription medications.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Nov 21, 2018.
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
General information
Key facts about L-Tryptophan 500 mg, straight from the product label.
| Brand | The Vitamin Shoppe |
|---|---|
| Barcode (UPC) | 766536025374 |
| Net contents | 60 Veggie Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Nov 21, 2018 |
| DSLD ID | 183563 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 L-Tryptophan 500 mg by The Vitamin Shoppe, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Tryptophan | 500 mg | -- |
Other ingredients: Vegetable capsule, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide
Tap any ingredient to jump to its full detail below.
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.
General Statements
Specialty
Mood Relaxation
Visit www.vitaminshoppe.com or call 1-800-223-1216 for more information and to reorder.
FDA Statement of Identity
Dietary Supplement
Formulation
Gluten free Dairy free Soy free Nut free
Does not contain: Gluten, sugar, salt, preservatives, artificial colors or flavors.
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Storage
Store in a cool, dry place.
Precautions
Keep out of reach of children.
Tamper evident Do not use if outer seal is broken or missing.
Warning: Consult your healthcare provider prior to use if you are pregnant, nursing, taking any medication or have any medical conditions.
Do not use with alcohol or when operating heavy machinery.
Suggested/Recommended/Usage/Directions
Directions: Take one (1) veggie capsule daily, preferably with a meal.
General
Item No. VS-2537 1658210 FS 37
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Tryptophan 500 mg by The Vitamin Shoppe label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in L-Tryptophan 500 mg by The Vitamin Shoppe
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Veggie Capsule(s) Dosage formCapsule Amounts shown are per serving.
L-Tryptophan
Interacts with394 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...
L-Tryptophan monograph & interactionsOther (inactive) ingredients: Vegetable capsule, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.
L-Tryptophan 500 mg by The Vitamin Shoppe Drug Interactions
HelloPharmacist Interaction Report
L-Tryptophan 500 mg by The Vitamin Shoppe interacts with two major drug categories: central nervous system (CNS) depressants and serotonergic drugs.
The most serious concern is with CNS depressants — combining this supplement with sedating medications (like sleep aids, opioids, or alcohol) could add up to dangerously strong drowsiness and sedation. L-Tryptophan itself causes fatigue and drowsiness, so the effect compounds.
Read the full breakdown — every affected drug type, severity by severity
The second major category is serotonergic drugs — antidepressants, migraine medications, and others that work through serotonin. L-Tryptophan is a building block for serotonin, so taking it with these drugs could amplify serotonin-related side effects, including the rare but serious serotonin syndrome and narrowing of blood vessels in the brain (cerebral vasoconstriction).
Altogether, these interactions span 394 individual medications. Before you start this supplement, run your exact medications — especially any sleep aids, pain relievers with opioids, anxiety or depression medications, or migraine treatments — through the checker on this page or talk with your doctor or pharmacist.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Tryptophan 500 mg?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in L-Tryptophan 500 mg interact with 394 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Tryptophan 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Tryptophan
AcepromazineAtravet
How Acepromazine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acepromazine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Butalbital, CodeineBancap w/ Codeine
How Acetaminophen, Butalbital, Codeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Butalbital, Codeine interactionAcetaminophen, Butalbital, Codeine PhosphatePhrenilin #3
How Acetaminophen, Butalbital, Codeine Phosphate interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Butalbital, Codeine Phosphate interactionAcetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
How Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionAcetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
How Acetaminophen, Caffeine, Codeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Caffeine, Codeine interactionAcetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
How Acetaminophen, Caffeine, Codeine, Salicylamide interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Caffeine, Codeine, Salicylamide interactionAcetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
How Acetaminophen, Caffeine, Dihydrocodeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Caffeine, Dihydrocodeine interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanSerotonergic Drugs, Cns Depressants Major
Interaction Summary
Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
Read the full L-tryptophan + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, OpiumHista-Derfule
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanSerotonergic Drugs, Cns Depressants Major
Interaction Summary
Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
Read the full L-tryptophan + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interactionAcetaminophen, Chlorzoxazone, CodeineAcetazone Forte C8, Parafon Forte C8
How Acetaminophen, Chlorzoxazone, Codeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Chlorzoxazone, Codeine interactionAcetaminophen, CodeineTylenol No.3, Tylenol w/ Codeine
How Acetaminophen, Codeine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Codeine interactionAcetaminophen, Codeine, DoxylamineMersyndol
How Acetaminophen, Codeine, Doxylamine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Codeine, Doxylamine interactionAcetaminophen, Codeine, MethocarbamolAcetaminophen, Codeine, Methocarbamol, Robaxacet 8
How Acetaminophen, Codeine, Methocarbamol interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Codeine, Methocarbamol interactionAcetaminophen, Dichloralantipyrine, IsomethepteneAmidrine, Midchlor, Migquin, Migratine
How Acetaminophen, Dichloralantipyrine, Isometheptene interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Dichloralantipyrine, Isometheptene interactionAcetaminophen, Dichloralphenazone, IsomethepteneMidrin
How Acetaminophen, Dichloralphenazone, Isometheptene interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Dichloralphenazone, Isometheptene interactionAcetaminophen, Dichlorophenazone, IsometheptaneIsocom
How Acetaminophen, Dichlorophenazone, Isometheptane interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Dichlorophenazone, Isometheptane interactionAcetaminophen, DiphenhydramineTylenol PM, Tylenol PM Ex Strength
How Acetaminophen, Diphenhydramine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Diphenhydramine interactionAcetaminophen, Diphenhydramine, PseudoephedrineChildren's Tylenol Allergy, Cold Control, Contac Night Allergy Relief
How Acetaminophen, Diphenhydramine, Pseudoephedrine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Diphenhydramine, Pseudoephedrine interactionAcetaminophen, HydrocodoneAnexsia, Anodynos DHC, Azdone, Co-Gesic, Doucet, Lorcet +9 more
How Acetaminophen, Hydrocodone interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Hydrocodone interactionAcetaminophen, MeperidineDemerol APAP
How Acetaminophen, Meperidine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants, Serotonergic Drugs Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Meperidine interactionAcetaminophen, OxycodonePercocet, Roxicet, Tylox, Xartemis XR
How Acetaminophen, Oxycodone interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Oxycodone interactionAcetaminophen, PentazocineTalacen
How Acetaminophen, Pentazocine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Pentazocine interactionAcetaminophen, PropoxypheneDarvocet-N 100, Darvocet-N 50, E-Lor, Wygesic
How Acetaminophen, Propoxyphene interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetaminophen, Propoxyphene interactionAcetazolamideAk-Zol, Diamox
How Acetazolamide interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Acetazolamide interactionAlfentanilAlfenta
How Alfentanil interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Alfentanil interactionAlprazolamNiravam, Xanax
How Alprazolam interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Alprazolam interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAminoglutethimideCytadren
How Aminoglutethimide interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Aminoglutethimide interactionAminophylline, Amobarbital, EphedrineAmesec
How Aminophylline, Amobarbital, Ephedrine interacts with L-Tryptophan 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-tryptophanCns Depressants Major
Interaction Summary
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Read the full L-tryptophan + Aminophylline, Amobarbital, Ephedrine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Tryptophan 500 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
L-Tryptophan
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.
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.
Brand information
Manufacturer and brand details for L-Tryptophan 500 mg, from the product label.
The Vitamin Shoppe
See all The Vitamin Shoppe products- Name
- Vitamin Shoppe, Inc.
- City
- Secaucus
- State
- NJ
- ZipCode
- 07094
- Phone Number
- 1-800-223-1216
- Web Address
- www.vitaminshoppe.com
L-Tryptophan 500 mg by The Vitamin Shoppe: Common Questions
Does L-Tryptophan 500 mg by The Vitamin Shoppe interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will L-Tryptophan actually help my mood or sleep?
What are the common side effects?
Is it safe during pregnancy?
Can I take this while breastfeeding?
What happened with the EMS scare I've heard about?
Why does this interact with so many medications?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Tryptophan 500 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind L-Tryptophan 500 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
L-Tryptophan 500 mg'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 18 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.
L-tryptophan 18 references
- Messiha FS. Fluoxetine: adverse effects and drug-drug interactions. J Toxicol Clin Toxicol 1993;31:603-30. PubMed
- 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
- Lieberman HR, Corkin S, Spring BJ. The effects of dietary neurotransmitter precursors on human behavior. Am J Clin Nutr 1985;42:366-70. PubMed
- 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.
- 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
- Philen RM, Hill RH, Flanders WD, et al. Tryptophan contaminants associated with eosinophilia-myalgia syndrome. Am J Epidemiol 1993;138:154-9. PubMed
- 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
- Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
- 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..
- 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
- 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
- Shaw K, Turner J, Del Mar C. Tryptophan and 5-hydroxytryptophan for depression. Cochrane Database Syst Rev 2002;(1):CD003198. PubMed
- 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.
- 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.
- Shapiro S. Epidemiologic studies of the association of L-tryptophan with the eosinophilia-myalgia syndrome: a critique. J Rheumatol Suppl 1996;46:44-58.
- Mayeno AN, Gleich GJ. The eosinophilia-myalgia syndrome: lessons from Germany. Mayo Clin Proc 1994;69:702-4. PubMed
- Carr L, Ruther E, Berg PA, Lehnert H. Eosinophilia-myalgia syndrome in Germany: an epidemiologic review. Mayo Clin Proc 1994;69:620-5. PubMed
- 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
Parts of this content are provided by the Therapeutic Research Center, LLC.
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.
© 2021 Therapeutic Research Center, LLC