L-Lysine 1,000 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Lysine 1,000 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-Lysine 1,000 mg is a dietary supplement by Nature's Truth with 1 active ingredient. Its ingredients are commonly taken for cold sores (herpes labialis), genital herpes outbreaks, supporting protein and collagen formation.Based on those ingredients, 1 medication has a known interaction with it, the most serious rated minor. The ingredients most likely to interact are L-Lysine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against L-Lysine 1,000 mg by Nature's Truth
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine 1,000 mg by Nature's Truth — 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-Lysine 1,000 mg by Nature's Truth
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-lysine 1,000 mg, an amino acid your body uses to build and repair tissue. The inactive ingredients — dicalcium phosphate, plant cellulose, stearic acid, croscarmellose, magnesium stearate, silica, and cellulose — are excipients that form and stabilize the tablet.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis). The evidence isn't established for other uses listed here — child growth, pressure ulcers, and diabetic foot ulcers — so we don't have enough reliable data to say whether it helps with those.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses, but high amounts may cause stomach upset, abdominal pain, diarrhea, and indigestion. Long-term safety at high doses isn't well studied.
One case report linked high-dose lysine to kidney inflammation progressing to chronic kidney failure, though this is rare. Supplement safety in pregnancy and breastfeeding hasn't been well studied, so talk with your doctor or pharmacist before using this product if you're pregnant or nursing.
Lysine from food is fine; the caution applies to supplements.
Meds to double-check
Minor interactions only
If you take 5-HT4 agonists (medications for certain GI motility conditions), let your pharmacist know before starting this product — lysine may reduce how well they work.
The bottom line
Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Only minor medication interactions are documented, and safety information is well characterized.
L-lysine may be worth considering if you get cold sores and want to try a supplement with modest evidence behind it. If you take medications for bowel motility or GI conditions, check with your pharmacist first.
Pregnant or breastfeeding? Talk with your doctor 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 Sep 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-Lysine 1,000 mg, straight from the product label.
| Brand | Nature's Truth |
|---|---|
| Barcode (UPC) | 840093101624 |
| Net contents | 100 Coated Caplet(s) |
| Market status | On market |
| Date entered into DSLD | Sep 25, 2025 |
| DSLD ID | 339754 |
| Product type | Amino Acid/protein |
| Supplement form | Other (e.g. Tea Bag) |
| Dietary claims / uses | Nutrient, All Other |
| 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-Lysine 1,000 mg by Nature's Truth, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 1000 mg | -- |
Other ingredients: Dicalcium Phosphate, Plant Cellulose, Stearic Acid, Croscarmellose, Magnesium Stearate, Silica, Cellulose
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
Directions: For adults, take one (1) coated caplet up to three times daily, preferably on an empty stomach.
Formulation
Free of Gluten, wheat, yeast, milk, lactose, soy, artificial color, artificial flavor, artificial sweetener, preservatives.
Our non-GMO Pledge Visit our website
Free form
Non-GMO Gluten Free
Vegan
Precautions
Warning: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.
If any adverse reactions occur, immediately stop using this product and consult your doctor. If seal under cap is damaged or missing, do not use.
Keep out of reach of children.
Storage
Store in cool, dry place.
Brand IP Statement(s)
Copyright 2024 Nature's Truth LLC
Seals/Symbols
Our non-GMO Pledge Visit our website
100% Quality Satisfaction Guarantee
Formula
Essential amino acid
Free form amino acid
FDA Statement of Identity
Dietary Supplement
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine 1,000 mg by Nature's Truth 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-Lysine 1,000 mg by Nature's Truth
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Coated Caplet(s) Dosage formOther (e.g. Tea Bag) Servings per container100 Amounts shown are per serving.
L-Lysine
Interacts with1 drug
Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to t...
L-Lysine monograph & interactionsOther (inactive) ingredients: Dicalcium Phosphate, Plant Cellulose, Stearic Acid, Croscarmellose, Magnesium Stearate, Silica, Cellulose. These complete the product’s ingredient list but are not active constituents.
L-Lysine 1,000 mg by Nature's Truth Drug Interactions
HelloPharmacist Interaction Report
L-Lysine 1,000 mg by Nature's Truth has one documented interaction.
L-lysine may reduce the effects of 5-HT4 agonists — a class of medications used for certain GI conditions. The effect is minor based on animal research showing lysine acts as a partial blocker of the serotonin receptor these drugs target.
Read the full breakdown — every affected drug type, severity by severity
Although we've identified this interaction, it's worth checking your exact medications with the search tool on this page, especially if you take any drugs for bowel or GI motility.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine 1,000 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-Lysine 1,000 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine 1,000 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine 1,000 mg — through 1 ingredient. Tap an ingredient for the detail:
L-lysine5-ht4 Agonists Minor
Interaction Summary
Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Read the full L-lysine + Tegaserod interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Lysine 1,000 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-Lysine
5-Ht4 Agonists
Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Animal research suggests that L-lysine is a partial serotonin receptor 4 (5-HT4) antagonist and inhibits diarrhea induced by the 5-HT4 agonist, 5-hydroxytryptophane.
Brand information
Manufacturer and brand details for L-Lysine 1,000 mg, from the product label.
Nature's Truth
See all Nature's Truth products- Name
- Nature's Truth LLC
- City
- Bohemia
- State
- NY
- ZipCode
- 11716
- Phone Number
- 1-844-544-1030
- Web Address
- NaturesTruth.com
L-Lysine 1,000 mg by Nature's Truth: Common Questions
Does L-Lysine 1,000 mg by Nature's Truth interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-lysine really help with cold sores?
What side effects should I watch for?
Can I take this if I'm pregnant?
Is it safe to take long-term?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine 1,000 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-Lysine 1,000 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-Lysine 1,000 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 7 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.
Lysine 7 references
- Thein DJ, Hurt WC. Lysine as a prophylactic agent in the treatment of recurrent herpes simplex labialis. Oral Surg Oral Med Oral Pathol 1984;58:659-66. PubMed
- McCune MA, Perry HO, Muller SA, O'Fallon WM. Treatment of recurrent herpes simplex infections with L-lysine monohydrochloride. Cutis 1984;34:366-73.
- DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol 1984;120:48-51. DOI
- Milman N, Scheibel J, Jessen O. Lysine prophylaxis in recurrent herpes simplex labialis: a double-blind, controlled crossover study. Acta Derm Venereol 1980;60:85-7.
- Griffith RS, Walsh DE, Myrmel KH, et al. Success of L-lysine therapy in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Dermatologica 1987;175:183-90. DOI
- Lo JC, Chertow GM, Rennke H, Seifter JL. Fanconi's syndrome and tubulointerstitial nephritis in association with L-lysine ingestion. Am J Kidney Dis 1996;28:614-7. PubMed
- Smriga M, Torii K. L-Lysine acts like a partial serotonin receptor 4 antagonist and inhibits serotonin-mediated intestinal pathologies and anxiety in rats. Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15370-5.
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