L-Lysine Hydrochloride 1,000 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Lysine Hydrochloride 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 Hydrochloride 1,000 mg is a dietary supplement by Highland Laboratories 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 Hydrochloride 1,000 mg by Highland Laboratories
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine Hydrochloride 1,000 mg by Highland Laboratories — 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 Hydrochloride 1,000 mg by Highland Laboratories
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 at 1,000 mg per tablet. L-lysine is an amino acid — one of the building blocks your body uses to make proteins.
The tablet also includes inactive ingredients (maltodextrin, cellulose, vegetable stearate, silica, magnesium stearate, and calcium phosphate) that help form and preserve the tablet.
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—there isn't enough reliable evidence to know whether it works.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses, but high amounts may cause stomach upset, including abdominal pain, diarrhea, and indigestion. One case report linked long-term oral lysine to a serious kidney condition, though this is very rare.
Supplement safety in pregnancy hasn't been well studied — lysine from food is fine, but if you're considering a supplement, talk with your doctor first. There isn't enough data on supplement use while breastfeeding, so caution is advised; check with your doctor or pharmacist.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (used for certain gastrointestinal conditions), check with your doctor or pharmacist before starting 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.
L-lysine is a reasonable choice if you're looking to manage cold sores, where the evidence supports its use. If you take a 5-HT4 agonist for digestive issues, clear it with your doctor or pharmacist first.
If you're pregnant, breastfeeding, or taking high doses for a long time, talk it over with your own healthcare provider.
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 Oct 21, 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 Hydrochloride 1,000 mg, straight from the product label.
| Brand | Highland Laboratories |
|---|---|
| Barcode (UPC) | 768305971103 |
| Net contents | 100 Vegetarian Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Oct 21, 2017 |
| DSLD ID | 79659 |
| Product type | Other Combinations |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | All Other |
| 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 Hydrochloride 1,000 mg by Highland Laboratories, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine Hydrochloride | 1000 mg | -- |
| L-Lysine | 800 mg | -- |
Other ingredients: Maltodextrin, Cellulose, Vegetable Stearate, Silica, Magnesium Stearate, Calcium Phosphate
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.
Formula
Free-form L-Lysine Hydrochloride (1,000 mg.)
FDA Statement of Identity
A Dietary Supplement
Seals/Symbols
GMP Quality Assured Earth Friendly
General Statements
% Daily Value
Formulation
No soy, salt, yeast, gluten, milk & egg products, sugar, starch or preservatives.
Suggested/Recommended/Usage/Directions
One or more tablets daily, in between meals, preferably with fruit juice. More effective when taken with carbohydrates, not protein.
Brand IP Statement(s)
Our tablets are processed with special plant cellulose under the Sol-U-Tab process assuring each tablet is completely solubilized within minutes of swallowing.
General
PR 971
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine Hydrochloride 1,000 mg by Highland Laboratories 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 Hydrochloride 1,000 mg by Highland Laboratories
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Vegetarian 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 & interactions- › L-Lysine
Other (inactive) ingredients: Maltodextrin, Cellulose, Vegetable Stearate, Silica, Magnesium Stearate, Calcium Phosphate. These complete the product’s ingredient list but are not active constituents.
L-Lysine Hydrochloride 1,000 mg by Highland Laboratories Drug Interactions
HelloPharmacist Interaction Report
Highland Laboratories L-Lysine Hydrochloride 1,000 mg has one documented drug interaction.
Through its L-lysine content, it 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 blocker of the serotonin receptor that these drugs target, which could make them less effective.
Read the full breakdown — every affected drug type, severity by severity
Altogether, these interactions span 1 individual medication. If you take a 5-HT4 agonist, check with your doctor or pharmacist before starting this supplement to make sure the timing and dose work for you.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine Hydrochloride 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 Hydrochloride 1,000 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine Hydrochloride 1,000 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine Hydrochloride
TegaserodZelnorm
How Tegaserod interacts with L-Lysine Hydrochloride 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 Hydrochloride 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 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 Hydrochloride 1,000 mg, from the product label.
L-Lysine Hydrochloride 1,000 mg by Highland Laboratories: Common Questions
Does L-Lysine Hydrochloride 1,000 mg by Highland Laboratories 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 might I notice?
Can I take this if I'm pregnant?
Is L-lysine safe for long-term use?
Will this help with wound healing or growth?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine Hydrochloride 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 Hydrochloride 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 Hydrochloride 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