L-Threonine 500 mg Capsules Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Threonine 500 mg Capsules 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-Threonine 500 mg Capsules is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for general amino acid/protein support, muscle and tissue health, immune support.Based on those ingredients, 3 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Threonine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against L-Threonine 500 mg Capsules by BulkSupplements.com
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Threonine 500 mg Capsules by BulkSupplements.com — 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-Threonine 500 mg Capsules by BulkSupplements.com
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-threonine, an amino acid your body normally gets from protein-containing foods. The capsule itself is made from gelatin.
Does it work?
Couldn't assess
The evidence for threonine supplements is sparse. For ALS (Lou Gehrig's disease), it appears possibly ineffective based on available data.
For multiple sclerosis, familial spastic paraparesis, and spasticity, we don't have enough reliable evidence to say whether it works or not.
How safe is it?
Well-documented data
Threonine from food is safe, but supplements at higher doses haven't been well studied. In clinical trials, some people reported headache or minor stomach upset, including diarrhea, gas, or constipation.
Because supplement safety in pregnancy and breastfeeding hasn't been well studied, the safety data advises against use in those situations unless a clinician advises otherwise.
Meds to double-check
Major interaction found
If you take NMDA antagonist medications, check them against our interaction tool before using this product — threonine may reduce how well they work. No other medication interactions are documented for the ingredients we could check.
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.
This is a single-ingredient supplement of an amino acid. It may appeal to people researching neurological conditions, but the evidence for its effectiveness is limited or absent.
If you take NMDA antagonist medications, check with us or your pharmacist before adding it. Talk to your doctor or pharmacist if you're pregnant, breastfeeding, or taking any 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 Apr 24, 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-Threonine 500 mg Capsules, straight from the product label.
| Brand | BulkSupplements.com |
|---|---|
| Barcode (UPC) | X003Z1FNXL |
| Net contents | 120 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Apr 24, 2025 |
| DSLD ID | 331191 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, 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-Threonine 500 mg Capsules by BulkSupplements.com, 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.
Formula
L-Threonine Capsules 500 mg per serving
Suggested/Recommended/Usage/Directions
Suggested Use: As a dietary supplement, take 1 capsule daily, or as directed by a physician.
Formulation
Free of: added sugar, soy, dairy, yeast, gluten, additives
Storage
Store in a dry, cool place
FDA Disclaimer Statement
Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.
Precautions
Always consult a physician before taking any dietary supplement.
Keep out of reach of children.
General Statements
New Scan Me
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Threonine 500 mg Capsules by BulkSupplements.com 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-Threonine 500 mg Capsules by BulkSupplements.com
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 container120 Amounts shown are per serving.
L-Threonine
Interacts with3 drugs
Threonine is an essential amino acid your body needs but cannot make, so you must get it from food or supplements. Most people get plenty from a norma...
L-Threonine monograph & interactionsOther (inactive) ingredients: Gelatin. These complete the product’s ingredient list but are not active constituents.
L-Threonine 500 mg Capsules by BulkSupplements.com Drug Interactions
HelloPharmacist Interaction Report
L-Threonine 500 mg by BulkSupplements.com contains one active ingredient that does interact with a specific class of medications.
Threonine raises glycine levels in your central nervous system, and glycine enhances NMDA receptors. This means threonine might decrease how well NMDA antagonists (a class of medications that block these receptors) work for you.
If you take any drug in this class, you'll want to check it against our tool below before starting this supplement.
Read the full breakdown — every affected drug type, severity by severity
No other medication interactions are documented for this ingredient in our data. That said, the absence of documented interactions isn't a guarantee that none exist — it just means we don't hold interaction data for them.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Threonine 500 mg Capsules?
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-Threonine 500 mg Capsules interact with 3 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Threonine 500 mg Capsules interact with drugs. Each result below shows which ingredient is responsible. L-Threonine
MemantineEbixa
How Memantine interacts with L-Threonine 500 mg Capsules — through 1 ingredient. Tap an ingredient for the detail:
L-threonineNmda Antagonists Major
Interaction Summary
Theoretically, threonine might decrease the effects of NMDA antagonists.
Read the full L-threonine + Memantine interactionMemantine HydrochlorideNamenda
How Memantine Hydrochloride interacts with L-Threonine 500 mg Capsules — through 1 ingredient. Tap an ingredient for the detail:
L-threonineNmda Antagonists Major
Interaction Summary
Theoretically, threonine might decrease the effects of NMDA antagonists.
Read the full L-threonine + Memantine Hydrochloride interactionMemantine, DonepezilNamzaric
How Memantine, Donepezil interacts with L-Threonine 500 mg Capsules — through 1 ingredient. Tap an ingredient for the detail:
L-threonineNmda Antagonists Major
Interaction Summary
Theoretically, threonine might decrease the effects of NMDA antagonists.
Read the full L-threonine + Memantine, Donepezil interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Threonine 500 mg Capsules 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-Threonine
Nmda Antagonists
Theoretically, threonine might decrease the effects of NMDA antagonists.
Threonine increases central nervous system (CNS) glycine levels. Glycine seems to bind a site on NMDA receptors and enhance the activity of the receptors.
Brand information
Manufacturer and brand details for L-Threonine 500 mg Capsules, from the product label.
BulkSupplements.com
See all BulkSupplements.com products- Name
- BulkSupplements.com
- Street Address
- 7511 Eastgate Rd
- City
- Henderson
- State
- NV
- ZipCode
- 89011
- Web Address
- BulkSupplements.com
L-Threonine 500 mg Capsules by BulkSupplements.com: Common Questions
Does L-Threonine 500 mg Capsules by BulkSupplements.com interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-threonine actually work for ALS or multiple sclerosis?
Can I take this if I'm pregnant or breastfeeding?
What side effects should I watch for?
Is this supplement well studied?
What is L-threonine and why would I take it?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Threonine 500 mg Capsules 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-Threonine 500 mg Capsules’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
L-Threonine 500 mg Capsules'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 4 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.
Threonine 4 references
- Tandan R, Bromberg MB, Forshew D, et al. A controlled trial of amino acid therapy in amyotrophic lateral sclerosis: I. Clinical, functional, and maximum isometric torque data. Neurology 1996;47:1220-6. PubMed
- Lee A, Patterson V. A double blind study of L-threonine in patients with spinal spasticity. Acta Neurol Scand 1993;88:334-8. PubMed
- Blin O, Pouget J, Aubrespy G, et al. A double-blind placebo controlled trial of L-threonine in amyotrophic lateral sclerosis. J Neurol 1992;239:79-81.
- Roufs JB. L-threonine as a symptomatic treatment for amyotrophic lateral sclerosis (ALS). Med Hypotheses 1991;34:20-3. 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