L-Lysine 1000 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Lysine 1000 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 1000 mg is a dietary supplement by Puritan's Pride 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 1000 mg by Puritan's Pride
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine 1000 mg by Puritan's Pride — 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 1000 mg by Puritan's Pride
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 a single active ingredient: L-lysine, an amino acid your body uses to build and repair tissues. It comes as a 1000 mg dose in a capsule form.
The inactive ingredients are cellulose, carnauba wax, silica, glycerin, magnesium stearate, and stearic acid — standard capsule fillers and binders.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis) — the research suggests it may help, but the evidence isn't definitive. For other uses like child growth, pressure ulcers, and diabetic foot ulcers, there isn't enough reliable evidence in our data to say whether it works.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses. At high amounts, it may cause stomach upset, abdominal pain, diarrhea, or indigestion — and long-term safety at high doses hasn't been well studied.
There's one rare case report of high-dose oral lysine linked to kidney inflammation that progressed to chronic kidney damage, though this is not established as a common risk. Lysine from food is fine in pregnancy, but supplement safety during pregnancy isn't well studied — check with your doctor first.
There isn't enough data on supplement use while breastfeeding, so caution is advised.
Meds to double-check
Minor interactions only
Before taking this product, check with your doctor or pharmacist if you take a 5-HT4 agonist — lysine may reduce its effectiveness. No other interactions are documented for the ingredient we could check.
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 if the evidence pans out for you. If you take a 5-HT4 agonist for digestive issues, confirm with your doctor or pharmacist that this supplement won't interfere.
Stick to typical doses and talk it over with your healthcare provider if you're pregnant, breastfeeding, or taking any medications.
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 Sep 25, 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 1000 mg, straight from the product label.
| Brand | Puritan's Pride |
|---|---|
| Barcode (UPC) | 074312160110 |
| Net contents | 60 Coated Caplet(s) |
| Market status | On market |
| Date entered into DSLD | Sep 25, 2024 |
| DSLD ID | 318291 |
| Product type | Amino Acid/protein |
| Supplement form | Other (e.g. Tea Bag) |
| Dietary claims / uses | Nutrient, All Other |
| Intended target group(s) | Vegetarian, 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 1000 mg by Puritan's Pride, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 1000 mg | -- |
Other ingredients: Cellulose, Carnauba Wax, Silica, Glycerin, Magnesium Stearate, Stearic Acid
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
L-lysine 1000 mg Free form
Formulation
Vegetarian
No artificial color, flavor or sweetener, no sugar, no starch, no milk, no lactose, no soy, no gluten, no wheat, no yeast, no fish. Sodium free.
Contains ingredients that may result in a variation of color and appearance over time.
FDA Statement of Identity
Amino Acid Supplement
Suggested/Recommended/Usage/Directions
Directions: For adults, take one (1) caplet up to two times daily, preferably on an empty stomach.
General Statements
Puritan's Pride supplements are produced from the finest raw materials under stringent quality standards. State-of-the-art manufacturing and packaging facilities ensure you the highest quality nutritional supplements money can buy. When it comes to your health...choose the best.
Different color Same product
To reorder item # 6011 www.puritan.com
Precautions
Warning: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.
Discontinue use and consult your doctor if any adverse reactions occur.
Keep out of reach of children.
Do not use if seal under cap is broken or missing.
Storage
Store at room temperature.
Brand IP Statement(s)
Copyright 2022 Puritan's Pride, Inc.
Seals/Symbols
QA Quality Assured
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine 1000 mg by Puritan's Pride 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 1000 mg by Puritan's Pride
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Caplet(s) Dosage formOther (e.g. Tea Bag) Servings per container60 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: Cellulose, Carnauba Wax, Silica, Glycerin, Magnesium Stearate, Stearic Acid. These complete the product’s ingredient list but are not active constituents.
L-Lysine 1000 mg by Puritan's Pride Drug Interactions
HelloPharmacist Interaction Report
Puritan's Pride L-Lysine 1000 mg has documented interactions through its L-lysine content with one medication type.
The most serious concern is a Minor interaction with 5-HT4 agonists (drugs used for certain digestive issues) — lysine may reduce how well these medications work by blocking the serotonin receptor they depend on.
Read the full breakdown — every affected drug type, severity by severity
No other medication interactions are documented in our data for this ingredient. That said, absence of documented interactions isn't a guarantee none exist.
Run your exact medications through the search tool on this page to be sure.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine 1000 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 1000 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine 1000 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine 1000 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 1000 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 L-Lysine 1000 mg, from the product label.
Puritan's Pride
See all Puritan's Pride products- Name
- Puritan's Pride, Inc.
- City
- Holbrook
- State
- NY
- ZipCode
- 11741
- Phone Number
- 1-800-645-1030
- Web Address
- www.puritan.com
L-Lysine 1000 mg by Puritan's Pride: Common Questions
Does L-Lysine 1000 mg by Puritan's Pride interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-lysine actually work for cold sores?
What side effects might I get from taking L-lysine?
Is it safe to take L-lysine while pregnant?
Can I take L-lysine while breastfeeding?
How much L-lysine should I take?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine 1000 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 1000 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 1000 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