L-Lysine Pharmaceutical Grade Ingredients & Drug Interactions
by Swanson
What is this page for?
First and foremost: checking L-Lysine Pharmaceutical Grade 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 Pharmaceutical Grade is a dietary supplement by Swanson 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 Pharmaceutical Grade by Swanson
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine Pharmaceutical Grade by Swanson — 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 Pharmaceutical Grade by Swanson
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, a naturally occurring amino acid. Lysine is an essential nutrient your body uses for protein building and immune function, but it doesn't make enough on its own — you need it from food or supplements.
The capsule also holds two inactive ingredients (hypromellose and calcium laurate) that help hold it together.
Does it work?
Insufficient evidence
L-Lysine is possibly effective for cold sores (herpes labialis). The evidence behind this use is still building, so results may vary from person to person.
For other uses listed — child growth, pressure ulcers, and diabetic foot ulcers — we don't have enough reliable evidence yet to say whether lysine helps.
How safe is it?
Well-documented data
L-Lysine is generally well tolerated at typical doses. Some people report stomach upset, diarrhea, abdominal pain, or indigestion, especially at higher amounts.
Long-term safety at high doses isn't well studied. There is one rare case report of kidney problems linked to oral lysine use, though this is not common.
For pregnancy and breastfeeding, lysine from food is fine, but supplement safety hasn't been well studied in either situation. Talk with your doctor before taking a lysine supplement if you're pregnant or breastfeeding — they can help you decide what's best for you and your baby.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist for gastrointestinal issues, double-check with your doctor or pharmacist before starting L-Lysine — the supplement may reduce its effect. For all other medications, no interactions are documented in our data, though that's not a guarantee none exist with your exact regimen.
The bottom line
Scorecard at a glanceFully disclosed formula with insufficient evidence for its stated purpose. Only minor medication interactions are documented, and safety information is well characterized.
L-Lysine may help with cold sores if you want to try it, and it's generally well tolerated at normal doses. If you take a 5-HT4 agonist (a drug for certain digestive issues), check with your doctor or pharmacist first — the supplement may reduce how well it works.
Pregnant or breastfeeding? Talk with your doctor before starting, since safety data is limited.
Always discuss new supplements 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 Feb 25, 2019.
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 Pharmaceutical Grade, straight from the product label.
| Brand | Swanson |
|---|---|
| Barcode (UPC) | 087614024523 |
| Net contents | 90 Veggie Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Feb 25, 2019 |
| DSLD ID | 193359 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years) |
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 Pharmaceutical Grade by Swanson, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Lysine | 500 mg | -- |
Other ingredients: Hypromellose, Calcium Laurate
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.
General Statements
Sourced from Japanese-based company Ajinomoto
Essential amino acid that supports the immune system and helps the body fight stress
Science-Backed Quality Since 1969
Immune Health
Suggested/Recommended/Usage/Directions
Suggested use: As a dietary supplement, take one veggie capsule per day with water on an empty stomach.
Brand IP Statement(s)
AjiPure and the AjiPure logo are registered trademarks of Ajinomoto, Inc.
Seals/Symbols
AjiPure amino acids
Precautions
Warning: For adults only.
Consult your physician before using this or any product if you are pregnant or nursing, taking medication or have a medical condition.
Keep out of reach of children.
Do not use if seal is broken.
Storage
Store in a cool, dry place.
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.
FDA Statement of Identity
Dietary Supplement
General
SWU452 Rev 0 08 13 18
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine Pharmaceutical Grade by Swanson 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 Pharmaceutical Grade by Swanson
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Veggie Capsule(s) Dosage formCapsule 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: Hypromellose, Calcium Laurate. These complete the product’s ingredient list but are not active constituents.
L-Lysine Pharmaceutical Grade by Swanson Drug Interactions
HelloPharmacist Interaction Report
L-Lysine Pharmaceutical Grade by Swanson has one documented interaction we know about.
Through its lysine content, this supplement may reduce the effects of 5-HT4 agonists — drugs used for certain gastrointestinal conditions. The interaction is rated Minor, meaning the effect is small, but it's worth checking if you take one of these medications.
Read the full breakdown — every affected drug type, severity by severity
If you're on a 5-HT4 agonist, talk with your doctor or pharmacist before starting lysine. They can help you time doses or monitor whether the supplement affects how your medication works.
Altogether, these interactions span 1 individual medication. You can search your exact drug below to see if it's affected.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine Pharmaceutical Grade?
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 Pharmaceutical Grade interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine Pharmaceutical Grade interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with L-Lysine Pharmaceutical Grade — 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 Pharmaceutical Grade 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 Pharmaceutical Grade, from the product label.
Swanson
See all Swanson products- Name
- Swanson Health Products
- City
- Fargo
- State
- ND
- ZipCode
- 58104
- Phone Number
- 1-800-437-4148
- Web Address
- swanson.com
L-Lysine Pharmaceutical Grade by Swanson: Common Questions
Does L-Lysine Pharmaceutical Grade by Swanson interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will L-Lysine help my cold sores?
What are the most common side effects?
Is L-Lysine safe to take long-term?
Can I take this if I'm pregnant or breastfeeding?
What is L-Lysine, and why do I need it?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine Pharmaceutical Grade 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 Pharmaceutical Grade’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 Pharmaceutical Grade'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