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 HBC Protocols 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 HBC Protocols
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tryptophan 500 mg by HBC Protocols — 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 HBC Protocols
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 involved in mood, sleep, and appetite regulation.
The capsule also contains magnesium stearate as an inactive ingredient (a lubricant used in manufacturing).
Does it work?
Not established
The evidence for L-tryptophan is mixed and limited. For depression, the data we hold shows it is possibly ineffective.
For anxiety, athletic performance, teeth grinding (bruxism), and premenstrual dysphoric disorder (PMDD), there is insufficient reliable evidence to rate whether it works. If you're considering this for one of those conditions, talk with your doctor about whether the evidence supports it for your situation.
How safe is it?
Well-documented data
L-Tryptophan is generally well tolerated when taken by mouth. The most common side effects are mild and include belching, diarrhea, drowsiness, dry mouth, flatulence, headache, heartburn, lightheadedness, nausea, stomach pain, blurred vision, and vomiting.
There is a serious historical concern: in 1989, a contaminated batch of L-tryptophan produced by a single Japanese manufacturer caused over 1,500 cases of eosinophilia-myalgia syndrome (EMS), a rare neurological disorder with skin changes, hair loss, and other serious symptoms. About 95% of those cases traced back to that one source; the product was recalled in 1990.
Modern L-tryptophan is subject to stricter oversight, but the history warrants caution. For pregnancy, the safety data is conflicting—some evidence suggests it may be possibly unsafe, so it's best to avoid it during pregnancy unless your doctor advises otherwise.
For breastfeeding, safety is not established, so avoid use while nursing. If you are pregnant, planning pregnancy, or breastfeeding, talk with your doctor or pharmacist before taking this product.
Meds to double-check
Major interaction found
Before taking L-Tryptophan, double-check with your doctor or pharmacist if you take any central nervous system depressants (sleep aids, benzodiazepines, opioids, or other sedating medications) or serotonergic drugs (antidepressants like SSRIs or SNRIs, certain migraine medications, or MAOIs). The combination could intensify drowsiness or raise the risk of serotonin syndrome.
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 be worth considering if you're interested in mood or sleep support and your doctor agrees—but it has major interactions with sleep aids, pain medications, and antidepressants, and the evidence for most uses is limited or unclear. Check your medications first, and talk with your doctor or pharmacist before starting, especially if you take anything for mood, sleep, or pain.
Avoid it during pregnancy and while breastfeeding.
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 Jun 23, 2017.
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 | HBC Protocols |
|---|---|
| Barcode (UPC) | 679840582214 |
| Net contents | 180 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Jun 23, 2017 |
| DSLD ID | 74991 |
| 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 |
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 HBC Protocols, sourced from the NIH Dietary Supplement Label Database.
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.
Formulation
No wheat, no gluten, no soy, no dairy, no egg, no fish/shellfish, no nuts/tree nuts, no corn.
Precautions
Warnings: Do not take this product if you are pregnant or breast feeding. If you are taking SSRI's (selective serotonin reuptake inhibitors) please contact your health care professional before taking this product.
Keep out of the reach of children.
FDA Statement of Identity
Dietary Supplement
General Statements
Discription Pharmaceutical grade-highest purity L-tryptophan is an essential amino acid therefore cannot be synthesized by the body and must be obtained via food or supplements. It plays an important role in promoting relaxation, sleep, good mood, and may also help reduce carbohydrate cravings.
Suggested/Recommended/Usage/Directions
Suggested use Take 1-3 capsules on an empty stomach 30 minutes before food consumption or sleep with water or fruit juice, or as directed by your health care consultant.
FDA Disclaimer Statement
This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Tryptophan 500 mg by HBC Protocols 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 HBC Protocols
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule Servings per container180 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: Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.
L-Tryptophan 500 mg by HBC Protocols Drug Interactions
HelloPharmacist Interaction Report
L-Tryptophan 500 mg by HBC Protocols interacts with two major drug categories through its single active ingredient.
The most serious concern is with central nervous system depressants (CNS depressants)—medications like benzodiazepines, sleep aids, and opioids—where L-tryptophan may add to drowsiness and sedation. The product itself can cause fatigue and drowsiness on its own, so combining it with these drugs could intensify that effect.
Read the full breakdown — every affected drug type, severity by severity
The second major interaction is with serotonergic drugs (antidepressants like SSRIs, SNRIs, and MAOIs, as well as certain migraine medications). L-Tryptophan is a building block your body uses to make serotonin.
Adding it on top of drugs that also increase serotonin carries a theoretical risk of serotonin syndrome—a condition with symptoms like agitation, rapid heart rate, muscle rigidity, and fever—and potentially cerebral vasoconstriction (narrowing of blood vessels in the brain). Altogether, these interactions span 394 individual medications.
Before you start this product, run your exact medications through the checker on this page. If you take anything for sleep, anxiety, pain, or mood, talk it over with your doctor or pharmacist first.
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
AmitriptylineElavil
How Amitriptyline 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 + Amitriptyline interactionAmitriptyline, ChlordiazepoxideLimbitrol DS
How Amitriptyline, Chlordiazepoxide 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 + Amitriptyline, Chlordiazepoxide interactionAmitriptyline, PerphenazineEtrafon, Etrafon-A, Etrafon-Forte, Triavil
How Amitriptyline, Perphenazine 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 + Amitriptyline, Perphenazine interactionAmobarbitalAmytal
How Amobarbital 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 + Amobarbital interactionAmobarbital, Ephedrine SulfateEphedrine & Amytal
How Amobarbital, Ephedrine Sulfate 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 + Amobarbital, Ephedrine Sulfate interactionAmobarbital, SecobarbitalTuinal
How Amobarbital, Secobarbital 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 + Amobarbital, Secobarbital interactionAprobarbital, Butabarbital, PhenobarbitalTriple Barbital
How Aprobarbital, Butabarbital, Phenobarbital 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 + Aprobarbital, Butabarbital, Phenobarbital interactionAripiprazoleAbilify, Abilify Maintena, Abilify Mycite
How Aripiprazole 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 + Aripiprazole interactionAripiprazole LauroxilAristada, Aristada Initio Kit
How Aripiprazole Lauroxil 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 + Aripiprazole Lauroxil interactionAspirin, Butalbital, Caffeine, Codeine PhosphateFiorinal w/ Codeine
How Aspirin, Butalbital, Caffeine, 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 + Aspirin, Butalbital, Caffeine, Codeine Phosphate interactionAspirin, Caffeine, Codeine PhosphateAnacin w/ Codeine
How Aspirin, Caffeine, 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 + Aspirin, Caffeine, Codeine Phosphate interactionAspirin, Caffeine, Dihydrocodeine BitartrateSynalgos DC
How Aspirin, Caffeine, Dihydrocodeine Bitartrate 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 + Aspirin, Caffeine, Dihydrocodeine Bitartrate interactionAspirin, Caffeine, HydrocodoneDamason-P
How Aspirin, Caffeine, 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 + Aspirin, Caffeine, Hydrocodone interactionAspirin, Caffeine, Phenacetin, PropoxypheneMargesic Comp. 65
How Aspirin, Caffeine, Phenacetin, 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 + Aspirin, Caffeine, Phenacetin, Propoxyphene interactionAspirin, Carisoprodol, Codeine PhosphateSoma Compound w/ Codeine
How Aspirin, Carisoprodol, 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 + Aspirin, Carisoprodol, Codeine Phosphate interactionAspirin, Codeine PhosphateAspirin w/ Codeine
How Aspirin, 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 + Aspirin, Codeine Phosphate interactionAspirin, Codeine Phosphate, MethocarbamolRobaxisal C
How Aspirin, Codeine Phosphate, 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 + Aspirin, Codeine Phosphate, Methocarbamol interactionAspirin, Codeine Phosphate, PhenobarbitalPhenaphen
How Aspirin, Codeine Phosphate, Phenobarbital 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 + Aspirin, Codeine Phosphate, Phenobarbital interactionAspirin, Diphenhydramine, PhenylpropanolamineAlka Seltzer Plus Night Time Effervescent
How Aspirin, Diphenhydramine, Phenylpropanolamine 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 + Aspirin, Diphenhydramine, Phenylpropanolamine interactionAspirin, Ethoheptazine, MeprobamateEquagesic
How Aspirin, Ethoheptazine, Meprobamate 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 + Aspirin, Ethoheptazine, Meprobamate interactionAspirin, HydrocodoneAlor 5 500, Lortab ASA
How Aspirin, 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 + Aspirin, Hydrocodone interactionAspirin, OxycodonePercodan
How Aspirin, 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 + Aspirin, Oxycodone interactionAspirin, PentazocineTalwin Compound
How Aspirin, 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 + Aspirin, Pentazocine interactionAtropine, Hyoscyamine, PhenobarbitalHypnaldyne
How Atropine, Hyoscyamine, Phenobarbital 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 + Atropine, Hyoscyamine, Phenobarbital interactionAtropine, Hyoscyamine, Phenobarbital, ScopolamineBarbidonna No. 2, Belladonna Phenobarbital
How Atropine, Hyoscyamine, Phenobarbital, Scopolamine 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 + Atropine, Hyoscyamine, Phenobarbital, Scopolamine interactionAtropine, Hyoscyamine, Scopolamine, PhenobarbitalBarbeloid, Donnatal #2, Donphen
How Atropine, Hyoscyamine, Scopolamine, Phenobarbital 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 + Atropine, Hyoscyamine, Scopolamine, Phenobarbital interactionAtropine, PhenobarbitalAnthrocol
How Atropine, Phenobarbital 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 + Atropine, Phenobarbital interactionAtropine, MeperidineAtropine, Meperidine
How Atropine, 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 + Atropine, Meperidine interactionAtropine, Morphine SulfateAtropine, Morphine Sulfate
How Atropine, Morphine Sulfate 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 + Atropine, Morphine Sulfate interactionBelladona Extract, PhenobarbitalChardonna-2
How Belladona Extract, Phenobarbital 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 + Belladona Extract, Phenobarbital 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.
HBC Protocols
See all HBC Protocols products- Name
- HBC Protocols, Inc.
- Street Address
- 8205 Santa Monica Blvd. Suite 472
- City
- Los Angeles
- State
- California
- ZipCode
- 90046
- Phone Number
- 888.497.3742
- Web Address
- ww.hbcprotocols.com
L-Tryptophan 500 mg by HBC Protocols: Common Questions
Does L-Tryptophan 500 mg by HBC Protocols interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-Tryptophan actually help with sleep or mood?
What are the most common side effects?
Is L-Tryptophan safe after the 1989 contamination scare?
Can I take this while pregnant or breastfeeding?
What is L-Tryptophan and what does it do?
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