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Dietary supplement

L-Tryptophan 1500 mg Ingredients & Drug Interactions

by NusaPure

Capsule Category: Amino Acid/protein
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

L-Tryptophan 1500 mg is a dietary supplement by NusaPure 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.

HelloPharmacist Scorecard of L-Tryptophan 1500 mg by NusaPure

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

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

NusaPure L-Tryptophan contains one active ingredient: L-tryptophan at 1500 mg per capsule. This is an amino acid your body uses to produce serotonin, a neurotransmitter tied to mood and sleep.

The capsule also contains cellulose and magnesium stearate as inactive ingredients (binders and fillers).

Does it work?

Couldn't assess
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 assessable

This is a single-ingredient L-tryptophan product and its label doesn't state a use — see L-tryptophan's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence for L-tryptophan is mixed and limited. For depression, it's rated possibly ineffective—the data doesn't support it as a reliable treatment.

For anxiety, athletic performance, teeth grinding (bruxism), and premenstrual dysphoric disorder (PMDD), we don't have enough reliable evidence to rate whether it works. If you're considering it for any of these, talk it over with your doctor about whether the evidence supports it for your situation.

The evidence, ingredient by ingredient L-tryptophan

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-Tryptophan is generally well tolerated orally, though a number of people report belching, diarrhea, drowsiness, dry mouth, flatulence, headache, heartburn, lightheadedness, nausea, stomach pain, blurred vision, and vomiting. The supplement has a troubled past: in 1989, over 1,500 cases of a rare neurological disorder called eosinophilia-myalgia syndrome (EMS) were linked to L-tryptophan, though nearly all traced to contaminated product from a single Japanese manufacturer.

The FDA restricted over-the-counter L-tryptophan imports after that recall, so modern products should be safer—but the history is worth knowing. For pregnancy, safety data is inconsistent: one source rates it likely safe, another rates it possibly unsafe.

During breastfeeding, safety is not established. Because the pregnancy data conflicts and lactation data is thin, talk with your doctor or pharmacist before taking this if you're pregnant or nursing.

Side effects, ingredient by ingredient L-tryptophan

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — L-tryptophan.
  • The most serious interaction on file is rated Major.
  • For scale: 394 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 L-Tryptophan, double-check with your doctor or pharmacist if you take any CNS depressants (sleep aids, sedatives, opioids, antihistamines, or alcohol) or serotonergic drugs (antidepressants, migraine medications like triptans, or tramadol). These are the medication types with documented interactions—CNS depressants at major severity, serotonergic drugs at moderate severity.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Major medication interactions have been identified, and safety information is well characterized.

L-Tryptophan may be worth considering if you're interested in supporting mood or sleep naturally, but the evidence for depression and anxiety isn't strong. The bigger picture: it can make you drowsy and may interact with sedatives and antidepressants, so it's not a product to take without checking first with your own doctor or pharmacist.

Its past safety scare was tied to contamination, not the ingredient itself, but it's worth knowing about.

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, 2021.

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 L-Tryptophan 1500 mg, straight from the product label.

Brand NusaPure
Barcode (UPC) X001WQ419D
Net contents 200 Veg Cap(s)
Market status On market
Date entered into DSLD Mar 25, 2021
DSLD ID 246730
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
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 L-Tryptophan 1500 mg by NusaPure, 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:
3 Veggie Capsule(s)
Maximum serving Sizes:
3 Veggie Capsule(s)
Servings per container
66
UPC/BARCODE
X001WQ419D
IngredientAmount% DV
L-Tryptophan1500 mg--

Other ingredients: Cellulose, Magnesium Stearate

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

Suggested Use: Take three (3) capsules daily, preferably with meals.

Precautions

Caution: For adults only.

Consult physician if pregnant, nursing, taking medication (especially antidepressants such as SSRIs and MAOI inhibitors), or have a medical condition.

May cause drowsiness. Do not use with alcoholic beverages or while operating heavy machinery.

Do not use if safety seal is damaged or missing.

Keep out of reach of children.

Allergen Information: Contains no artificial coloring, artificial flavor, yeast, corn, milk or milk derivatives, lactose, salt, sodium, soy, sugar, gluten, or wheat. Produced in a GMP facility that processes other ingredients containing these allergens.

Storage

Store in cool dry place. Avoid excessive heat or moisture.

General Statements

Please recycle.

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.

Seals/Symbols

Premium Quality Assembled in USA GMO Free Made with non-GMO Ingredients Gluten Free FDA Registered Facility

Manufactured in a cGMP Inspected Facility

Formulation

GMO Free Made with non-GMO Ingredients Gluten Free FDA Registered Facility

Assembled in USA Tested Supports positive mood & restful sleep Supports healthy immune function Supports circulation & stress management Max Strength

Allergen Information: Contains no artificial coloring, artificial flavor, yeast, corn, milk or milk derivatives, lactose, salt, sodium, soy, sugar, gluten, or wheat.

Natural color variation may occur in this product.

Formula

L-Tryptophan 1500 mg per serving

FDA Statement of Identity

Dietary Supplement

See for yourself

L-Tryptophan 1500 mg by NusaPure label

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

What’s inside

The Ingredients in L-Tryptophan 1500 mg by NusaPure

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size3 Veggie Capsule(s) Dosage formCapsule Servings per container66 Amounts shown are per serving.

L-Tryptophan

Interacts with
394 drugs
1500 mg per serving

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for...

L-Tryptophan monograph & interactions

Other (inactive) ingredients: Cellulose, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Tryptophan 1500 mg by NusaPure Drug Interactions

Want to check YOUR meds against L-Tryptophan 1500 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 checker
394Drugs
248 Major 146 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Tryptophan 1500 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-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
The maker

Brand information

Manufacturer and brand details for L-Tryptophan 1500 mg, from the product label.

NusaPure

See all NusaPure products
Name
Gmax Central LLC
Street Address
4700 Millenia Boulevard, Suite 175 PMB 92909
City
Orlando
State
FL
ZipCode
32839
Pharmacist Counseling Corner

L-Tryptophan 1500 mg by NusaPure: Common Questions

Does L-Tryptophan 1500 mg by NusaPure interact with any medications?
Yes. Based on its ingredients, L-Tryptophan 1500 mg has a known interaction with 394 medications, including 248 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Tryptophan 1500 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
Will L-tryptophan really help with my mood or sleep?
The evidence is weak. For depression, it's rated possibly ineffective. For anxiety and sleep problems, we don't have enough solid research to say whether it works. Your doctor is the best person to discuss whether it makes sense for you.
What are the most common side effects?
Many people tolerate it well, but some report belching, diarrhea, drowsiness, dry mouth, gas, headache, heartburn, lightheadedness, nausea, stomach pain, blurred vision, and vomiting. Drowsiness is the one you're most likely to notice.
Is it safe to take while pregnant or breastfeeding?
The pregnancy data is mixed—one source says likely safe, another says possibly unsafe—so there's no clear answer. For breastfeeding, safety isn't established. Talk with your doctor or pharmacist before taking it if you're pregnant or nursing; they can help you weigh what we do and don't know.
I heard L-tryptophan was dangerous. Is that still true?
In 1989, contaminated L-tryptophan from one Japanese manufacturer caused over 1,500 cases of a rare neurological disorder. The FDA restricted imports afterward, so modern products should be safer. But the history is real and worth being aware of.
Can I take this with my antidepressant?
Not without checking first. L-Tryptophan boosts serotonin, and combining it with antidepressants (which also raise serotonin) might increase the risk of serotonin syndrome. Your own doctor or pharmacist needs to weigh your specific medications and situation.

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

Not sure if L-Tryptophan 1500 mg is safe with your meds?

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Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-Tryptophan 1500 mg label
Sources

Sources & How We Checked

L-Tryptophan 1500 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.

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
  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.
  14. Horwitz RI, Daniels SR. Bias or biology: evaluating the epidemiologic studies of L-tryptophan and the eosinophilia-myalgia syndrome. J Rheumatol Suppl 1996;46:60-72.
  15. Shapiro S. Epidemiologic studies of the association of L-tryptophan with the eosinophilia-myalgia syndrome: a critique. J Rheumatol Suppl 1996;46:44-58.
  16. Mayeno AN, Gleich GJ. The eosinophilia-myalgia syndrome: lessons from Germany. Mayo Clin Proc 1994;69:702-4. PubMed
  17. Carr L, Ruther E, Berg PA, Lehnert H. Eosinophilia-myalgia syndrome in Germany: an epidemiologic review. Mayo Clin Proc 1994;69:620-5. PubMed
  18. Ullrich SS, Fitzgerald PCE, Giesbertz P, Steinert RE, Horowitz M, Feinle-Bisset C. Effects of intragastric administration of tryptophan on the blood glucose response to a nutrient drink and energy intake, in lean and obese men. Nutrients 2018;10(4). pii: PubMed

See these in context on the L-tryptophan monograph →

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

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