L-Lysine Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Lysine 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 is a dietary supplement by Woodstock Vitamins 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 by Woodstock Vitamins
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine by Woodstock Vitamins — 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
Ask the Pharmacist
A licensed pharmacist will answer your question by email — free, usually within 24 hours.
Got it — thank you!
A licensed pharmacist will answer within 24 hours. Keep an eye on your email (worth checking spam, just in case).
HelloPharmacist Scorecard of L-Lysine by Woodstock Vitamins
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
Woodstock Vitamins L-Lysine is a single-ingredient supplement — just L-lysine, an amino acid your body needs. The capsule also contains inactive ingredients (HPMC, medium-chain triglyceride oil, stearic acid, magnesium stearate, and silica), which are standard binders and fillers that help form and stabilize the supplement.
Does it work?
Not established
L-Lysine is possibly effective for cold sores (herpes labialis) — the evidence suggests it may help, though it's not ironclad. For other uses listed — child growth, pressure ulcers, and diabetic foot ulcers — we don't have enough reliable evidence to say whether it works.
If you're thinking about it for cold sores, talk with your doctor or pharmacist about whether a trial makes sense for you.
How safe is it?
Well-documented data
L-Lysine is generally well tolerated at typical doses. Some people report stomach upset, diarrhea, or abdominal pain when they take it orally.
High amounts may cause more stomach trouble, and long-term safety at high doses hasn't been thoroughly studied. There's one rare case report of oral lysine linked to a serious kidney issue, though this is extremely uncommon.
If you're pregnant, supplement safety isn't well studied — lysine from food is fine, but check with your doctor before taking a supplement. If you're breastfeeding, there isn't enough reliable data on safety, so caution is advised.
Talk it over with your doctor or pharmacist for personalized guidance.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (a medication for digestive motility), check with your doctor or pharmacist before adding this supplement — lysine may reduce its effectiveness. No other medication interactions are documented in our data for L-Lysine.
The bottom line
Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Only minor medication interactions are documented, and safety information is well characterized.
L-Lysine is a simple, single-ingredient supplement that may help with cold sores. It's generally well tolerated, though some people experience stomach upset.
If you take a 5-HT4 agonist or are pregnant or breastfeeding, talk with your doctor or pharmacist before starting. For any other questions about how it fits into your routine, your doctor or pharmacist can help.
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 24, 2020.
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, straight from the product label.
| Brand | Woodstock Vitamins |
|---|---|
| Barcode (UPC) | 669439835968 |
| Net contents | 90 Vegetarian Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Mar 24, 2020 |
| DSLD ID | 215889 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Vegetarian, 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 by Woodstock Vitamins, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 1 Gram(s) | -- |
Other ingredients: HPMC, Medium-Chain Triglyceride Oil, Stearic Acid, Magnesium Stearate, Silica
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
Directions: Preferably on an empty stomach, take one to two capsules three times a day, or as directed by your healthcare practitioner.
Precautions
Consult your healthcare practitioner prior to use. Do not use if tamper seal is damaged.
Individuals taking medication should discuss potential interactions with their healthcare practitioner.
Storage: Keep tightly closed in a cool, dry place out of reach of children.
Formulation
L-Lysine is an amino acid essential in human physiology. Lysine is vital for normal growth and for the manufacture of collagen, a substance important for healthy skin, bones, tendons, and cartilage. Supplemental lysine may be appropriate for individuals on a high-arginine diet.
Does not contain: Wheat, gluten, corn, yeast, soy, animal or dairy products, fish, shellfish, peanuts, tree nuts, egg, ingredients derived from genetically modified organisms (GMOs), artificial colors, artificial sweeteners, or artificial preservatives.
Manufactured in a GMP compliant facility.
FDA Disclaimer Statement
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.
Storage
Storage: Keep tightly closed in a cool, dry place out of reach of children.
Formula
An essential amino acid
FDA Statement of Identity
Dietary Supplement
General Statements
Vegetarian Caps This package is completely recyclable
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine by Woodstock Vitamins 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 by Woodstock Vitamins
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule Servings per container45 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: HPMC, Medium-Chain Triglyceride Oil, Stearic Acid, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.
L-Lysine by Woodstock Vitamins Drug Interactions
HelloPharmacist Interaction Report
L-Lysine by Woodstock Vitamins has one documented interaction: it may theoretically reduce the effects of 5-HT4 agonists (a drug class used for certain digestive and motility issues).
Animal research suggests lysine acts as a partial blocker of the serotonin receptor that these drugs target, which could lower their effectiveness.
Read the full breakdown — every affected drug type, severity by severity
Although this is the only interaction our data shows for L-Lysine, it's Minor in severity. Still, if you take a 5-HT4 agonist, mention this supplement to your doctor or pharmacist before starting it.
Altogether, these interactions span 1 individual medication. Use the search tool below to check your exact medications.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine?
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 interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine — 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 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, from the product label.
Woodstock Vitamins
See all Woodstock Vitamins products- Name
- Village Vitality LLC
- Street Address
- 79 Tinker Street Fl 2
- City
- Woodstock
- State
- NY
- ZipCode
- 12498
- Phone Number
- (845) 521-7455
- Web Address
- www.WoodstockVitamins.com
L-Lysine by Woodstock Vitamins: Common Questions
Does L-Lysine by Woodstock Vitamins interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-Lysine actually help with cold sores?
What side effects might I notice?
Is it safe to take while pregnant?
Is it safe to take while breastfeeding?
How much should I take?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine 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’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'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