L-Lysine HCL Ingredients & Drug Interactions
What is this page for?
First and foremost: checking L-Lysine HCL 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 HCL is a dietary supplement by BulkSupplements.com 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 HCL by BulkSupplements.com
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Lysine HCL by BulkSupplements.com — 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 HCL by BulkSupplements.com
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, an amino acid your body uses for protein synthesis and immune function. There are no inactive ingredients listed.
Does it work?
Moderate evidence
L-lysine is possibly effective for cold sores (herpes labialis). The evidence supporting its use for growth in children, pressure ulcers, or diabetic foot ulcers is currently insufficient — we don't have enough reliable data to rate it for those uses.
How safe is it?
Well-documented data
L-lysine is generally well tolerated at typical doses. At high amounts, it may cause stomach upset including abdominal pain, diarrhea, and indigestion — and long-term safety at large doses hasn't been well studied.
There's a rare case report of kidney inflammation linked to oral lysine use, though this was one individual. During pregnancy, lysine from food is fine, but supplement safety hasn't been well studied, so check with your doctor first.
While breastfeeding, there isn't enough reliable information to know whether supplements are safe — talk 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 certain gastrointestinal conditions), confirm with your doctor or pharmacist before using this product — lysine may reduce its effectiveness. No other medication interactions are documented for the ingredients 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 makes sense if you're dealing with cold sores and want to try a possibly effective supplement. If you take a 5-HT4 agonist for a gut condition, check with your doctor or pharmacist before starting, since lysine may reduce how that medication works.
Pregnant or breastfeeding? Your doctor or pharmacist can give you the guidance that fits your situation.
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 Oct 22, 2021.
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 HCL, straight from the product label.
| Brand | BulkSupplements.com |
|---|---|
| Barcode (UPC) | X000HHF5FR |
| Net contents | 1 kg; 35.3 Oz(s) |
| Market status | On market |
| Date entered into DSLD | Oct 22, 2021 |
| DSLD ID | 254567 |
| Product type | Amino Acid/protein |
| Supplement form | Powder |
| Dietary claims / uses | 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 HCL by BulkSupplements.com, 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.
General Statements
Clean & pure bulk supplements
FDA Disclaimer Statement
Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.
Precautions
Always consult a physician before taking any dietary supplement.
Keep out of reach of children.
Formulation
Free of: Added sugar, soy, dairy, yeast, gluten, additives
Suggested/Recommended/Usage/Directions
Suggested Use: As a dietary supplement, take 1 capsule once or twice daily, or as directed by a physician.
Storage
Store in a dry, cool place
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Lysine HCL by BulkSupplements.com 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 HCL by BulkSupplements.com
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size750 mg Dosage formPowder Servings per container1333 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 HCL by BulkSupplements.com Drug Interactions
HelloPharmacist Interaction Report
L-Lysine HCL by BulkSupplements.com contains one active ingredient, lysine, which has a documented interaction with 5-HT4 agonists (a class of medications used for certain gastrointestinal conditions).
Lysine may theoretically reduce how well these drugs work. Animal studies suggest lysine acts as a partial antagonist to serotonin receptor 4 and can inhibit the diarrhea-causing effects of 5-HT4 agonists — meaning it could blunt the intended effect of your medication.
Read the full breakdown — every affected drug type, severity by severity
Although this is rated Minor severity, it's worth checking your exact medications before you start. If you take a 5-HT4 agonist, talk with your doctor or pharmacist before adding lysine to make sure it won't interfere with your treatment.
Altogether, these interactions span 1 individual medication.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Lysine HCL?
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 HCL interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in L-Lysine HCL interact with drugs. Each result below shows which ingredient is responsible. L-Lysine Hydrochloride
TegaserodZelnorm
How Tegaserod interacts with L-Lysine HCL — 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 HCL 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 HCL, from the product label.
BulkSupplements.com
See all BulkSupplements.com products- Name
- BulkSupplements.com
- Street Address
- 7511 Eastgate Rd
- City
- Henderson
- State
- NV
- ZipCode
- 89011
- Web Address
- BulkSupplements.com
L-Lysine HCL by BulkSupplements.com: Common Questions
Does L-Lysine HCL by BulkSupplements.com interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-lysine really help with cold sores?
What side effects might I get from L-lysine?
Is it safe to take L-lysine while pregnant?
Can I take L-lysine while breastfeeding?
Will L-lysine help me grow taller or heal pressure ulcers?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Lysine HCL 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 HCL’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 HCL'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