L-Lysine 1,000 mg Unflavored Ingredients & Drug Interactions
by Nutricost
What is this page for?
First and foremost: checking L-Lysine 1,000 mg Unflavored 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 1,000 mg Unflavored is a dietary supplement by Nutricost 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 1,000 mg Unflavored by Nutricost
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine 1,000 mg Unflavored by Nutricost — 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 1,000 mg Unflavored by Nutricost
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 serving. L-lysine is an amino acid — one of the building blocks your body uses to make protein.
There are no inactive ingredients listed in this formulation.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis), according to the evidence we have. For other uses like helping children grow, preventing pressure ulcers, or healing diabetic foot ulcers, the evidence is not established — we don't have enough reliable data to rate it one way or the other.
How safe is it?
Well-documented data
L-lysine from food sources is fine. As a supplement, lysine is generally well tolerated at typical doses, but high amounts may cause stomach upset, abdominal pain, diarrhea, or indigestion.
Long-term safety hasn't been well studied. For pregnancy: supplement safety during pregnancy isn't well studied, so check with your doctor before using it — getting lysine from food is a different story.
For breastfeeding: there isn't enough reliable information on supplement use while nursing, so talk it over with your doctor or pharmacist for personalized guidance.
Meds to double-check
Minor interactions only
If you take 5-HT4 agonists (medications that work on serotonin receptors in the gut), check with your doctor or pharmacist before starting this supplement — lysine may reduce their effectiveness.
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 for possibly effective support for cold sores and want a single-ingredient option. Keep in mind that high doses may upset your stomach, and long-term safety data is limited.
If you take any 5-HT4 agonist medication, check with your doctor or pharmacist before starting. If you're pregnant, breastfeeding, or have kidney concerns, talk it through with your healthcare provider first.
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 22, 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 1,000 mg Unflavored, straight from the product label.
| Brand | Nutricost |
|---|---|
| Barcode (UPC) | 702669937771 |
| Net contents | 35 Ounce(s); 2.2 Pound(s); 1 Kilogram(s) |
| Market status | On market |
| Date entered into DSLD | Mar 22, 2024 |
| DSLD ID | 306322 |
| 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 |
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 1,000 mg Unflavored by Nutricost, sourced from the NIH Dietary Supplement Label Database.
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
Suggested use: As a dietary supplement, mix 1 scoop daily with 6-10 oz of water or as directed by your healthcare professional.
Formulation
Third Party Tested
Non-GMO Gluten-free
Made and quality tested in the USA with globally sourced ingredients.
Non-GMO Product
Precautions
Notice: For healthy individuals 18 years and older. Keep out of reach of children.
Consult a healthcare professional prior to use if you are pregnant or nursing, taking medication, or have a medical condition.
Do not use if safety seal broken or missing.
Storage
Notice: Store in a cool, dry place.
General Statements
Contents are sold by weight, not volume. Some settling may occur.
Formula
L-Lysine 1,000 mg per serving 1kg per container
FDA Statement of Identity
Dietary Supplement
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.
Seals/Symbols
Quality Nutricost Guaranteed Third Party Tested
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine 1,000 mg Unflavored by Nutricost 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 1,000 mg Unflavored by Nutricost
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Gram(s) Dosage formPowder Servings per container1000 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: None. These complete the product’s ingredient list but are not active constituents.
L-Lysine 1,000 mg Unflavored by Nutricost Drug Interactions
HelloPharmacist Interaction Report
Nutricost L-Lysine 1,000 mg interacts with one medication type through its L-lysine hydrochloride content.
The interaction is minor: lysine may theoretically reduce how well 5-HT4 agonists (a class of drugs that work on serotonin receptors in the gut) work. Animal research suggests lysine acts as a partial blocker of the serotonin receptor 4, which could dampen the effect of these medications.
Read the full breakdown — every affected drug type, severity by severity
Although the interaction is rated minor, if you take any 5-HT4 agonist medication, it's worth double-checking with your doctor or pharmacist before you start this supplement. They can advise whether the potential effect matters for your specific situation and whether timing or dosing adjustments are needed.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine 1,000 mg Unflavored?
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 1,000 mg Unflavored interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine 1,000 mg Unflavored interact with drugs. Each result below shows which ingredient is responsible. L-Lysine Hydrochloride
TegaserodZelnorm
How Tegaserod interacts with L-Lysine 1,000 mg Unflavored — 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 1,000 mg Unflavored 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 1,000 mg Unflavored, from the product label.
Nutricost
See all Nutricost products- Name
- Nutricost
- Street Address
- 351 E 1750 N
- City
- Vineyard
- State
- UT
- ZipCode
- 84059
- Phone Number
- (866) 438-3694
- Web Address
- www.nutricost.com
L-Lysine 1,000 mg Unflavored by Nutricost: Common Questions
Does L-Lysine 1,000 mg Unflavored by Nutricost interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will L-lysine actually help my cold sores?
What are the most common side effects?
Is it safe to take this while pregnant?
Can I take this while breastfeeding?
What exactly is L-lysine?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine 1,000 mg Unflavored 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 1,000 mg Unflavored’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 1,000 mg Unflavored'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