L-Lysine Ingredients & Drug Interactions
by XYMOGEN
What is this page for?
First and foremost: checking L-Lysine 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 is a dietary supplement by XYMOGEN 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 by XYMOGEN
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine by XYMOGEN — 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 by XYMOGEN
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, an amino acid your body uses for protein synthesis and immune function. L-lysine is found in foods like poultry, eggs, and dairy, and this supplement provides a concentrated dose.
The remaining ingredients—hydroxypropyl methylcellulose, medium chain triglyceride oil, stearic acid, magnesium stearate, and silica—are inactive excipients that form the capsule and aid absorption.
Does it work?
Moderate evidence
L-lysine is possibly effective for herpes labialis (cold sores). For other uses listed in the data—child growth, pressure ulcers, and diabetic foot ulcers—there isn't enough reliable evidence to rate its effectiveness, so we can't tell you whether it works for those.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses. At high doses, it may cause stomach upset, abdominal pain, diarrhea, or indigestion; long-term safety at elevated amounts hasn't been well studied.
There's one rare case report of oral lysine linked to kidney inflammation progressing to chronic kidney failure, though this is not established as a common risk. Supplement safety during pregnancy and breastfeeding isn't well studied, so check with your doctor or pharmacist before taking this while pregnant or nursing.
Lysine from food sources is fine; we just don't have enough data on the supplement form in these situations.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (a drug that boosts serotonin receptor activity, sometimes used for digestive problems), check with your pharmacist before starting L-lysine—it may reduce how well the medication works.
The bottom line
Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Only minor medication interactions are documented, and safety information is well characterized.
L-lysine is a good option if you're looking for support with cold sores, where it has some evidence behind it. If you take a 5-HT4 agonist (ask your pharmacist if you're unsure), let them know before starting this supplement.
Talk with your doctor or pharmacist before taking it during pregnancy or breastfeeding, and stick to typical doses to minimize stomach upset.
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 Feb 22, 2024.
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, straight from the product label.
| Brand | XYMOGEN |
|---|---|
| Barcode (UPC) | 871149003371 |
| Net contents | 90 Vegetarian Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Feb 22, 2024 |
| DSLD ID | 303737 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| 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-Lysine by XYMOGEN, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 1 Gram(s) | -- |
Other ingredients: Hydroxypropyl Methylcellulose, Medium Chain Triglyceride Oil, Stearic Acid, Magnesium Stearate, Silica
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: Preferably on an empty stomach, take one to two capsule three times a day, or as directed by your healthcare practitioner.
Precautions
Consult your healthcare practitioner prior to use.
Individuals taking medication should discuss potential interactions with their healthcare practitioner.
Do not use if tamper seal is damaged.
Storage: Keep closed in a cool, dry place, out of reach of children.
Formula
L-Lysine is an amino acid essential in human physiology. Lysine is vital for normal growth and for the manufacture of collagen, a substance important for healthy skin, bones, tendons, and cartilage. Supplemental lysine may be appropriate for individuals on a high-arginine diet.
An essential amino acid
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.
Storage
Storage: Keep closed in a cool, dry place, out of reach of children.
Formulation
Does Not Contain: Wheat, gluten, corn, yeast, soy, animal or dairy products, fish, shellfish, peanuts, tree nuts, egg, ingredients derived from genetically modified organisms (GMOs), artificial colors, artificial sweeteners, or artificial preservatives.
Vegetarian Caps
Brand IP Statement(s)
Copyright 2019 Xymogen
Xymogen Exclusive Professional Formulas
Seals/Symbols
Vegetarian Caps ePV (ePedigree Verification)
Third-Party Verified GMP Compliant
FDA Statement of Identity
Dietary Supplement
General Statements
Scan to Learn More! This package is completely recyclable
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine by XYMOGEN 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 by XYMOGEN
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 container45 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: Hydroxypropyl Methylcellulose, Medium Chain Triglyceride Oil, Stearic Acid, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.
L-Lysine by XYMOGEN Drug Interactions
HelloPharmacist Interaction Report
L-Lysine by XYMOGEN has one documented interaction: it may reduce the effects of 5-HT4 agonists (a class of drugs that boost serotonin receptor activity and are sometimes used for digestive issues).
Animal research suggests lysine acts as a partial antagonist to this receptor, which means it could theoretically blunt how well these medications work.
Read the full breakdown — every affected drug type, severity by severity
Additionally, this is a Minor interaction, and no other medication types are affected by lysine in our data. Altogether, these interactions span 1 individual medication.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine?
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 interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine — 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 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, from the product label.
XYMOGEN
See all XYMOGEN products- Name
- XYMOGEN Exclusive Professional Formulas
- Street Address
- 6900 Kingspointe Pkwy.
- City
- Orlando
- State
- FL
- ZipCode
- 32819
- Phone Number
- 800-647-6100
- Web Address
- www.xymogen.com
L-Lysine by XYMOGEN: Common Questions
Does L-Lysine by XYMOGEN interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will L-lysine help my cold sores?
What are the most common side effects?
Is L-lysine safe long-term?
Can I take this while pregnant?
Is it safe to breastfeed while taking L-lysine?
What's in this besides the lysine?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine 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’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'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