L-Lysine Powder 960 mg Ingredients & Drug Interactions
by Carlson
What is this page for?
First and foremost: checking L-Lysine Powder 960 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 Powder 960 mg is a dietary supplement by Carlson 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 Powder 960 mg by Carlson
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine Powder 960 mg by Carlson — 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 Powder 960 mg by Carlson
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 1 active ingredient: L-Lysine, an amino acid your body uses for protein synthesis and immune function. L-Lysine is supplied as a powder at 960 mg per serving.
There are no inactive ingredients listed.
Does it work?
Moderate evidence
L-Lysine is possibly effective for herpes labialis (cold sores) — that's where the best evidence sits. For child growth, pressure ulcers, and diabetic foot ulcers, the evidence isn't established enough for us to rate it.
How safe is it?
Well-documented data
L-Lysine is generally well tolerated at typical doses. High amounts may cause stomach upset, and long-term safety from supplements hasn't been well studied.
The most common side effects from oral lysine are abdominal pain, diarrhea, and indigestion. There is one case report of oral lysine linked to kidney inflammation progressing to chronic kidney failure, though this is rare.
For pregnancy, supplement safety hasn't been well studied — lysine from food is fine, but check with your doctor before taking a supplement. For breastfeeding, there isn't enough reliable information, so caution is advised.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist medication, check with your pharmacist before starting this supplement — lysine may reduce its effectiveness (Minor severity).
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.
If you're dealing with cold sores, L-Lysine may help. But if you take a 5-HT4 agonist medication, check with us first.
High doses and long-term use haven't been fully studied, so stick to typical amounts. Talk to your pharmacist if you're pregnant, breastfeeding, or on 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 Aug 22, 2025.
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 Powder 960 mg, straight from the product label.
| Brand | Carlson |
|---|---|
| Barcode (UPC) | 088395068850 |
| Net contents | 3.53 Ounce(s); 100 Gram(s) |
| Market status | On market |
| Date entered into DSLD | Aug 22, 2025 |
| DSLD ID | 337537 |
| Product type | Amino Acid/protein |
| Supplement form | Powder |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy 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 Powder 960 mg by Carlson, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 960 mg | -- |
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.
Brand IP Statement(s)
Carlson Providing the highest quality nutritional supplements since 1965
Formula
L-Lysine is an essential amino acid that promotes immune and tissue health, provides stress support, and is an important building block for protein.
Free-form amino acid
Precautions
Warning: Pregnant or lactating women or those with kidney problems should consult with their doctor before using this product.
Formulation
Potency & quality guaranteed An FDA regulated facility
This product may vary in appearance and consistency.
Immune function Stress support Tissue health
Gluten-free Milk/casein-free
Storage
This product is sold by weight not volume.
Keep bottle tightly closed. Store away from heat and moisture.
FDA Statement of Identity
Dietary Supplement
Suggested/Recommended/Usage/Directions
Directions: Adults: take 1/2 teaspoonful (one level scoopful) daily mixed into food or liquid.
FDA Disclaimer Statement
These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine Powder 960 mg by Carlson 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 Powder 960 mg by Carlson
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1.2 Gram(s) Dosage formPowder Servings per container83 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 & interactionsL-Lysine Powder 960 mg by Carlson Drug Interactions
HelloPharmacist Interaction Report
L-Lysine Powder 960 mg by Carlson has one documented interaction.
L-Lysine may reduce the effects of 5-HT4 agonists (a class of medications used to treat certain GI conditions). Animal research suggests lysine works as a partial serotonin receptor 4 antagonist and can inhibit diarrhea caused by 5-HT4 agonist drugs — meaning it could potentially make those medications less effective.
This is a Minor interaction.
Read the full breakdown — every affected drug type, severity by severity
Alto gether, this interaction spans 1 individual medication. If you take a 5-HT4 agonist, run it through the checker below before starting this supplement.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine Powder 960 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 Powder 960 mg interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine Powder 960 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine Powder 960 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 Powder 960 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 Powder 960 mg, from the product label.
Carlson
See all Carlson products- Name
- Carlson Division of J.R. Carlson Laboratories, Inc.
- City
- Lincolnshire
- State
- IL
- ZipCode
- 60069
- Phone Number
- 888-234-5656
- Web Address
- carlsonlabs.com
L-Lysine Powder 960 mg by Carlson: Common Questions
Does L-Lysine Powder 960 mg by Carlson interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-Lysine help with cold sores?
What are the side effects of L-Lysine?
Is L-Lysine safe during pregnancy?
Can I take L-Lysine while breastfeeding?
Is this just L-Lysine or does it have other ingredients?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine Powder 960 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 Powder 960 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 Powder 960 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