L-Lysine HCl 500 mg Ingredients & Drug Interactions
by Foods Plus
What is this page for?
First and foremost: checking L-Lysine HCl 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
L-Lysine HCl 500 mg is a dietary supplement by Foods Plus 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 Hydrochloride. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against L-Lysine HCl 500 mg by Foods Plus
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine HCl 500 mg by Foods Plus — 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 HCl 500 mg by Foods Plus
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 hydrochloride, an amino acid supplement at 500 mg per tablet. The inactive ingredients are microcrystalline cellulose, stearic acid, dicalcium phosphate, and magnesium stearate — typical tablet binders and fillers.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis). For other uses listed — child growth, pressure ulcers, and diabetic foot ulcers — the evidence we have is insufficient to rate whether it works.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses. At higher amounts, it may cause stomach upset (abdominal pain, diarrhea, indigestion).
Long-term safety at high doses hasn't been well studied. There is one case report of kidney inflammation and chronic kidney failure in a person taking oral lysine, though this is rare.
Regarding pregnancy and breastfeeding: lysine from food is fine, but supplement safety during pregnancy hasn't been well studied — check with your doctor first. There also isn't enough reliable information on supplement use while breastfeeding, so caution is advised.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist for digestive issues, check with your doctor or pharmacist before adding this supplement — 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.
This supplement may help with cold sores, though the evidence is modest. It's generally well tolerated, but high doses can upset your stomach, and its long-term safety profile isn't extensive.
If you take a 5-HT4 agonist medication, discuss this with your doctor or pharmacist before starting. Pregnant or breastfeeding people should talk it over with their healthcare provider given the limited safety data.
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 24, 2017.
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 HCl 500 mg, straight from the product label.
| Brand | Foods Plus |
|---|---|
| Barcode (UPC) | 717284006672 |
| Net contents | 60 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Mar 24, 2017 |
| DSLD ID | 71853 |
| 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, Dairy Free, Sugar 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 HCl 500 mg by Foods Plus, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine Hydrochloride | 500 mg | -- |
Other ingredients: Microcrystalline Cellulose, Stearic Acid, Dicalcium Phosphate, Magnesium Stearate
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: Take 1 tablet daily as a dietary supplement or as directed by a healthcare professional.
General
FP #667
Precautions
Keep out of reach of children.
Storage
Protect from heat, light and moisture. Store in a cool, dry place.
General Statements
Made in the U.S.A.
Helps fight cold sores
Since 1962
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.
Formulation
No sugar, starch, yeast, wheat, milk, soy, artificial colors, flavors or preservatives
Preservative free Non GMO Gluten-free
FDA Statement of Identity
Dietary Supplement
Formula
Essential amino acids
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine HCl 500 mg by Foods Plus 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 HCl 500 mg by Foods Plus
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 Hydrochloride
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 Hydrochloride monograph & interactionsOther (inactive) ingredients: Microcrystalline Cellulose, Stearic Acid, Dicalcium Phosphate, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.
L-Lysine HCl 500 mg by Foods Plus Drug Interactions
HelloPharmacist Interaction Report
L-Lysine HCl 500 mg by Foods Plus has one documented interaction.
Through its L-lysine content, it may reduce the effects of 5-HT4 agonists (a class of medications used to treat certain digestive issues). Animal research suggests lysine acts as a partial antagonist to these drugs, which could blunt their intended action.
Read the full breakdown — every affected drug type, severity by severity
If you take a 5-HT4 agonist, let your doctor or pharmacist know you're considering this supplement so they can monitor whether your medication is working as expected. 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 HCl 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 L-Lysine HCl 500 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine HCl 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine Hydrochloride
TegaserodZelnorm
How Tegaserod interacts with L-Lysine HCl 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-lysine Hydrochloride5-ht4 Agonists Minor
Interaction Summary
Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Read the full L-lysine Hydrochloride + Tegaserod interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Lysine HCl 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 Hydrochloride
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 HCl 500 mg, from the product label.
Foods Plus
See all Foods Plus products- Name
- Foods Plus
- Street Address
- 10 Henderson Drive
- City
- West Caldwell
- State
- New Jersey
- ZipCode
- 07006
L-Lysine HCl 500 mg by Foods Plus: Common Questions
Does L-Lysine HCl 500 mg by Foods Plus interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-lysine actually help with cold sores?
What side effects should I watch for?
Is it safe to take while pregnant?
Can I take this while breastfeeding?
Will this work for pressure ulcers or diabetic foot ulcers?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine HCl 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 L-Lysine HCl 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
L-Lysine HCl 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