L-Lysine HCl 500 mg Ingredients & Drug Interactions
by Windmill
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 Windmill 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 Windmill
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine HCl 500 mg by Windmill — 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 Windmill
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, 500 mg per tablet. L-lysine is an amino acid—one of the building blocks your body uses to make protein.
The inactive ingredients are microcrystalline cellulose, dicalcium phosphate, stearic acid, and magnesium stearate, which are standard tablet binders and fillers.
Does it work?
Moderate evidence
L-lysine is possibly effective for herpes labialis (cold sores). For other uses—child growth, pressure ulcers, and diabetic foot ulcers—the evidence we hold is insufficient to establish whether it works.
If you're thinking about L-lysine for cold sores, talk with your doctor or pharmacist about whether it's right for your situation.
How safe is it?
Well-documented data
L-lysine from food is safe, but supplement safety in pregnancy hasn't been well studied—check with your doctor before taking it if you're pregnant. There isn't enough reliable information on supplement use while breastfeeding either, so caution is advised and you should talk it over with your doctor or pharmacist.
At typical doses, L-lysine is generally well tolerated, though high amounts may cause stomach upset, diarrhea, abdominal pain, or indigestion. Long-term safety at high doses isn't well studied.
There is one case report of oral lysine associated with kidney inflammation progressing to chronic kidney failure, though this is rare.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (a medication for certain gastrointestinal issues), L-lysine may reduce how well it works—Minor severity. Check with your doctor or pharmacist before combining them.
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 help with cold sores. It's generally well tolerated at standard doses, but high amounts can cause stomach upset.
If you're pregnant or breastfeeding, check with your doctor first. And if you take any prescription medication—especially a 5-HT4 agonist—confirm there's no interaction with your pharmacist or doctor before you start.
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 23, 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 L-Lysine HCl 500 mg, straight from the product label.
| Brand | Windmill |
|---|---|
| Barcode (UPC) | 035046003180 |
| Net contents | 60 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Mar 23, 2012 |
| DSLD ID | 7261 |
| 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), 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 Windmill, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine Hydrochloride | 500 mg | -- |
Other ingredients: Microcrystalline Cellulose, Dicalcium Phosphate, Stearic Acid, 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.
General
ITEM #318 Tracking #01650602
Suggested/Recommended/Usage/Directions
Directions: Take one tablet daily as a dietary supplement or as directed by a healthcare professional.
Precautions
KEEP OUT OF REACH OF CHILDREN.
Protect from heat, light and moisture. Store at 15-30(0)C (59-86(0)F).
DO NOT PURCHASE IF SEAL IS BROKEN.
General Statements
MADE IN U.S.A.
Helps Fight Cold Sores*
FDA Disclaimer Statement
*This statement has 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
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 HCl 500 mg by Windmill 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 Windmill
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, Dicalcium Phosphate, Stearic Acid, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.
L-Lysine HCl 500 mg by Windmill Drug Interactions
HelloPharmacist Interaction Report
Windmill's L-Lysine HCl 500 mg may interact with medications through its L-lysine content.
The most serious documented interaction is Minor in severity: lysine may reduce the effects of 5-HT4 agonists (a class of drugs used for certain gastrointestinal conditions). Animal research suggests lysine acts as a partial antagonist to serotonin receptor 4 and can inhibit the diarrhea-inducing effects of 5-HT4 agonist medications.
Read the full breakdown — every affected drug type, severity by severity
Although we hold interaction data for L-lysine, this is the only affected medication type documented in our records. Altogether, these interactions span 1 individual medication.
If you take a 5-HT4 agonist or any other prescription medication, run it through the checker below before starting this supplement to confirm there's no concern with your specific drugs.
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.
Windmill
- Name
- Windmill Health Products
- City
- West Caldwell
- State
- New Jersey
- ZipCode
- 07006
L-Lysine HCl 500 mg by Windmill: Common Questions
Does L-Lysine HCl 500 mg by Windmill interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will L-lysine help me if I get cold sores?
Can I take this if I'm pregnant?
What side effects might I experience?
Is it safe to take while breastfeeding?
What is L-lysine and what does it do?
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