Natural L-Lysine 500 mg Ingredients & Drug Interactions
by Sunmark
What is this page for?
First and foremost: checking Natural L-Lysine 500 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
Natural L-Lysine 500 mg is a dietary supplement by Sunmark 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 Natural L-Lysine 500 mg by Sunmark
Ask about any prescription or over-the-counter medication and we check it for interactions with Natural L-Lysine 500 mg by Sunmark — 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 Natural L-Lysine 500 mg by Sunmark
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 to build proteins. Each tablet delivers 500 mg of L-lysine in the form of L-lysine monohydrochloride.
The other ingredients are inactive — cellulose, polyethylene glycol, magnesium stearate, croscarmellose sodium, and silicon dioxide — which help form and stabilize the tablet.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis). The evidence isn't strong enough yet to rate it for child growth, pressure ulcers, or diabetic foot ulcers — we don't have reliable data on whether it helps with those.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at normal doses. At high amounts, it may cause stomach upset, and long-term safety hasn't been thoroughly studied.
The most common side effects are abdominal pain, diarrhea, and indigestion. There's one case report of kidney problems linked to oral lysine, though this is rare.
Lysine from food is fine during pregnancy, but we don't have enough research on supplement safety during pregnancy or breastfeeding. Talk with your doctor or pharmacist before taking L-lysine if you're pregnant or nursing.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (a digestive medication), check with your doctor or pharmacist before starting this product — lysine may reduce how well it 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 worth considering if you get frequent cold sores and want a possibly effective option. If you take medications for digestive issues (5-HT4 agonists), check with your doctor or pharmacist first — this supplement might interfere with how they work.
At typical doses it's well tolerated, but don't use very high amounts without guidance.
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 26, 2012.
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 Natural L-Lysine 500 mg, straight from the product label.
| Brand | Sunmark |
|---|---|
| Barcode (UPC) | 010939377333 |
| Net contents | 100 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Apr 26, 2012 |
| DSLD ID | 7740 |
| Product type | Amino Acid/protein |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten 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 Natural L-Lysine 500 mg by Sunmark, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 500 mg | -- |
Other ingredients: L-Lysine Monohydrochloride, Cellulose, Polyethylene Glycol, Magnesium Stearate, Croscarmellose Sodium, 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.
General Statements
49348-053-10
PRODUCT BENEFIT Clear, healthy lips and mouth tissue*
USP has tested and verified ingredients, potency, and manufacturing process. USP sets official standards for dietary supplements. See www.uspverified.org
Healthy lips and mouth tissue may be affected by sun exposure, trauma, emotional anxiety, and high body temperature. Lysine, an amino acid, may be helpful in maintaining healthy lips and mouth tissue.* Lysine also helps calcium absorption, helps collagen and tissue renewal, and aids in the production of antibodies, hormones, and enzymes.*
Money Back Guarantee
FRESHNESS AND POTENCY GUARANTEED THROUGH:
Formulation
NO PRESERVATIVES ADDED NO LACTOSE NO ARTIFICIAL COLOR OR FLAVOR NO GLUTEN
Seals/Symbols
DIETARY SUPPLEMENT USP VERIFIED(TM)
McKESSON Empowering Healthcare
FDA Statement of Identity
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.
Suggested/Recommended/Usage/Directions
Suggested use: Take one tablet one to three times daily with a full glass of water, preferably after a meal.
Precautions
If pregnant, nursing or taking any medications, consult your healthcare professional before taking this product.
Keep out of the reach of children.
Storage
Keep in a cool dry place, tightly closed.
General
SUN4410A06
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Natural L-Lysine 500 mg by Sunmark 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 Natural L-Lysine 500 mg by Sunmark
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 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: L-Lysine Monohydrochloride, Cellulose, Polyethylene Glycol, Magnesium Stearate, Croscarmellose Sodium, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.
Natural L-Lysine 500 mg by Sunmark Drug Interactions
HelloPharmacist Interaction Report
Natural L-Lysine 500 mg by Sunmark interacts with one medication type.
Through its L-lysine content, this product may reduce the effects of 5-HT4 agonists — a class of drugs used to treat certain digestive issues. Animal research suggests lysine can partially block serotonin receptor 4, which is how these medications work.
Read the full breakdown — every affected drug type, severity by severity
If you take a 5-HT4 agonist, talk with your doctor or pharmacist before starting L-lysine to make sure the combination won't affect how your medication works. Altogether, these interactions span 1 individual medication.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Natural L-Lysine 500 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 Natural L-Lysine 500 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in Natural L-Lysine 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with Natural L-Lysine 500 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 Natural L-Lysine 500 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 Natural L-Lysine 500 mg, from the product label.
Sunmark
See all Sunmark products- Name
- McKesson
- Street Address
- One Post Street
- City
- San Francisco
- State
- CA
- ZipCode
- 94104
Natural L-Lysine 500 mg by Sunmark: Common Questions
Does Natural L-Lysine 500 mg by Sunmark 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 are the most common side effects?
Is it safe to take L-lysine if I'm pregnant?
Can I take L-lysine while breastfeeding?
Why is there so much other stuff in the tablet besides L-lysine?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Natural L-Lysine 500 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 Natural L-Lysine 500 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Natural L-Lysine 500 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