L-Tryptophan 1000 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Tryptophan 1000 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 1000 mg is a dietary supplement by Protocol For Life Balance 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 1000 mg by Protocol For Life Balance
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tryptophan 1000 mg by Protocol For Life Balance — 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 1000 mg by Protocol For Life Balance
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 1000 mg per tablet. L-Tryptophan is an amino acid your body uses to make serotonin, a chemical that affects mood and sleep.
The remaining ingredients — croscarmellose sodium, hydroxypropyl cellulose, stearic acid, magnesium stearate, vegetarian coating, and silicon dioxide — are inactive fillers and binders that help form and preserve the tablet.
Does it work?
Not established
The evidence for L-Tryptophan is mixed and limited. For depression, it's rated possibly ineffective based on available trials.
For anxiety, athletic performance, teeth grinding (bruxism), and premenstrual dysphoric disorder (PMDD), there isn't enough reliable evidence to know whether it works. If you're considering it for any of those reasons, talk with your doctor or pharmacist about whether the data supports it for your specific situation.
How safe is it?
Well-documented data
L-Tryptophan is generally well tolerated when you take it by mouth, but it does carry some cautions. The most common side effects are belching, diarrhea, drowsiness, dry mouth, flatulence, headache, heartburn, lightheadedness, nausea, stomach pain, blurred vision, and vomiting.
Rare serious side effects include eosinophilia-myalgia syndrome (EMS), a neurological disorder; nearly all cases traced back to contaminated L-Tryptophan from a single Japanese manufacturer in the late 1980s, which led to a U.S. recall and import limits in 1990. During pregnancy, there isn't enough safety data, so it's best avoided.
The same goes for breastfeeding — safety isn't established, so avoid it while nursing. If you're pregnant or breastfeeding and thinking about L-Tryptophan, talk with your pharmacist or doctor first.
Meds to double-check
Major interaction found
Before you take L-Tryptophan, double-check it with any CNS depressants you use — sedatives, sleep aids, opioids, antihistamines that cause drowsiness, or alcohol (Major interaction). Also check it against serotonergic drugs like most antidepressants, some pain relievers, and migraine treatments (Moderate interaction).
Use the medication checker on this page to be sure.
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 help some people, but the evidence for common uses like depression and anxiety is weak or absent. More importantly, it interacts significantly with CNS depressants and serotonergic drugs — so if you take sedatives, sleep aids, most antidepressants, or certain pain and migraine medications, check your exact drugs with us before starting.
Avoid it in pregnancy and while breastfeeding. Talk to your pharmacist about whether this is right for you.
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 Mar 25, 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
General information
Key facts about L-Tryptophan 1000 mg, straight from the product label.
| Brand | Protocol For Life Balance |
|---|---|
| Barcode (UPC) | 707359101692 |
| Net contents | 60 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Mar 25, 2025 |
| DSLD ID | 326452 |
| Product type | Amino Acid/protein |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, 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 1000 mg by Protocol For Life Balance, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Tryptophan | 1000 mg | -- |
Other ingredients: Croscarmellose Sodium, Hydroxypropyl Cellulose, Stearic Acid, Magnesium Stearate, Vegetarian Coating, 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.
Suggested/Recommended/Usage/Directions
Suggested usage: Take 1 tablet 1 to 2 times daily on an empty stomach, with final dose at bedtime, or as directed by your healthcare practitioner.
Formula
How it works: Tryptophan is an essential amino acid; therefore, it is not synthesized by the body and must be obtained from the diet. In the brain, tryptophan is converted into serotonin, a neurotransmitter involved in feelings of well-being, calmness, personal security, and relaxation. It also plays a role in the regulation of appetite and synchronization of sleep patterns.
Formulation
Every lot of Protocol For Life Balance L-Tryptophan is tested to be free of peak E and microbial contamination.
Encourages positive mood Supports relaxation & restful sleep
Non-GMO
Vegetarian/vegan
Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.
Natural color variation may occur in this product.
Precautions
Cautions/interactions: Tryptophan supplements may interact with CNS depressants, antidepressants (SSRIs, MAOIs), and other serotonergic agents such as St. John's Wort and 5-HTP. May cause drowsiness. Do not use with alcoholic beverages or while operating heavy machinery.
Consult your healthcare practitioner if you are taking medications or herbs, are pregnant/nursing, or if you have liver impairment.
Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.
FDA Statement of Identity
A Dietary Supplement
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.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Tryptophan 1000 mg by Protocol For Life Balance 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 1000 mg by Protocol For Life Balance
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container60 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: Croscarmellose Sodium, Hydroxypropyl Cellulose, Stearic Acid, Magnesium Stearate, Vegetarian Coating, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.
L-Tryptophan 1000 mg by Protocol For Life Balance Drug Interactions
HelloPharmacist Interaction Report
Protocol For Life Balance's L-Tryptophan 1000 mg does interact with medications.
The most serious concern is with CNS depressants — drugs that slow your brain and nervous system, like sedatives, sleep aids, opioids, and alcohol. L-Tryptophan can add to their drowsy and sedating effects, which the facts note as a Major-level interaction.
Read the full breakdown — every affected drug type, severity by severity
It also has a Moderate interaction with serotonergic drugs — medications that work on serotonin, including most antidepressants, some pain relievers, and migraine treatments. L-Tryptophan is a building block for serotonin in your body, so combining it with these drugs could boost serotonin effects beyond what's intended.
That raises the risk of serotonin syndrome (a serious condition with agitation, confusion, rapid heart rate, and high blood pressure) and cerebral vasoconstrictive disorders (narrowing of blood vessels in the brain).
Altogether, these interactions span 394 individual medications. Use the search tool on this page to check your exact prescriptions and over-the-counter medicines — including alcohol — before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Tryptophan 1000 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 1000 mg interact with 394 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Tryptophan 1000 mg interact with drugs. Each result below shows which ingredient is responsible. L-Tryptophan
AcepromazineAtravet
How Acepromazine interacts with L-Tryptophan 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 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 1000 mg, from the product label.
Protocol For Life Balance
See all Protocol For Life Balance products- Name
- Protocol For Life Balance
- Street Address
- 395 S. Glen Ellyn Rd.
- City
- Bloomingdale
- State
- IL
- ZipCode
- 60108
- Web Address
- protocolforlife.com
L-Tryptophan 1000 mg by Protocol For Life Balance: Common Questions
Does L-Tryptophan 1000 mg by Protocol For Life Balance interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
What is L-Tryptophan, and what's it supposed to do?
Can I take L-Tryptophan if I'm on an antidepressant?
What are the side effects?
Is it safe during pregnancy or breastfeeding?
Will L-Tryptophan help my anxiety or depression?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Tryptophan 1000 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 1000 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 1000 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.
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