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Dietary supplement

L-Lysine HCL 500 mg Ingredients & Drug Interactions

by BulkSupplements.com

Capsule Category: Amino Acid/protein
Most serious interaction: Minor
The interaction bottom line Most serious interaction: Minor

L-Lysine HCL 500 mg 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.

HelloPharmacist Scorecard of L-Lysine HCL 500 mg 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.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: L-lysine hydrochloride, 500 mg per capsule. Lysine is an amino acid — a building block your body uses for protein and other functions.

The capsule itself is made of hypromellose, an inactive ingredient that holds the lysine.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: amino acid for protein and collagen formation.
  • We looked for evidence on: Herpes labialis (cold sores), genital herpes, wound healing, bone health.
  • The strongest evidence on file: Lysine is rated "Possibly Effective" for Herpes labialis (cold sores) (Natural Medicines).

L-lysine is possibly effective for cold sores (herpes labialis) based on the evidence we hold. For other uses — child growth, pressure ulcers, and diabetic foot ulcers — the evidence isn't strong enough yet to say whether it works.

If you're considering it for cold sores, talk it over with your doctor or pharmacist to see if it makes sense for you.

The evidence, ingredient by ingredient Lysine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Lysine is generally well tolerated at typical doses. The most common side effects reported orally are stomach pain, diarrhea, and indigestion.

High amounts may cause stomach upset, and long-term safety from supplements hasn't been thoroughly studied. There's one case report of oral lysine linked to kidney inflammation and chronic kidney failure, though this is very rare.

If you're pregnant, the safety data on lysine supplements isn't established yet — lysine from food is fine, but talk with your doctor before taking a supplement. If you're breastfeeding, there isn't enough information to know either way, so check with your doctor or pharmacist for personalized advice.

Side effects, ingredient by ingredient Lysine

Meds to double-check

Minor interactions only
Known Interaction Concern · database check
Minor only

Only Minor-severity interactions are documented for these ingredients.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Lysine.
  • The most serious interaction on file is rated Minor.
  • For scale: 1 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

If you take 5-HT4 agonists (medications used for certain digestive and bowel conditions), let your doctor or pharmacist know you're considering lysine — it may reduce how well they work. No other interactions are documented for the ingredients we could check.

Check your own medication Run your meds through the checker above

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 may help with cold sores, though the evidence is moderate. It's generally well tolerated, but stomach upset can happen at higher doses, and long-term safety isn't fully known.

If you take any medications — especially 5-HT4 agonists for digestive problems — check with your pharmacist or doctor before starting.

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

At a glance

General information

Key facts about L-Lysine HCL 500 mg, straight from the product label.

Brand BulkSupplements.com
Net contents 100 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Oct 22, 2021
DSLD ID 254582
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy Free, Sugar Free
From the label
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 500 mg by BulkSupplements.com, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
100
IngredientAmount% DV
L-Lysine Hydrochloride500 mg--

Other ingredients: Hypromellose Capsules

Tap any ingredient to jump to its full detail below.

Label statements
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

Precautions

Warning: This product is not intended for use by those with a serious medical condition or pregnant or lactating women. Consult your physician before use.

Keep out of reach of children!

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.

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

Storage: Keep dry, cool & dark

See for yourself

L-Lysine HCL 500 mg by BulkSupplements.com label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in L-Lysine HCL 500 mg by BulkSupplements.com

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 container100 Amounts shown are per serving.

L-Lysine Hydrochloride

Interacts with
1 drug
500 mg per serving

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 & interactions

Other (inactive) ingredients: Hypromellose Capsules. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Lysine HCL 500 mg by BulkSupplements.com Drug Interactions

Want to check YOUR meds against L-Lysine HCL 500 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 checker
1Drugs
1 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Lysine HCL 500 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 Hydrochloride1 drug type · 1 drug

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.

Likelihood Unlikely Evidence D
The maker

Brand information

Manufacturer and brand details for L-Lysine HCL 500 mg, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Road
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

L-Lysine HCL 500 mg by BulkSupplements.com: Common Questions

Does L-Lysine HCL 500 mg by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, L-Lysine HCL 500 mg has a known interaction with 1 medication. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Lysine HCL 500 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Will L-lysine help my cold sores?
L-lysine is possibly effective for cold sores based on the evidence we have. That means some research supports it, but the data isn't conclusive yet. If you're thinking about trying it, chat with your doctor or pharmacist about whether it's worth a try for you.
What are the most common side effects?
Stomach pain, diarrhea, and indigestion are the most common side effects reported when taking lysine by mouth. High doses are more likely to cause stomach upset. If you notice any of these, you can lower your dose or stop and talk to your pharmacist.
Is L-lysine safe to take while pregnant?
Lysine from food is fine during pregnancy, but the safety of supplements during pregnancy hasn't been well studied. Check with your doctor before taking this supplement if you're pregnant — they can weigh the potential benefit against what we don't yet know.
Can I take this while breastfeeding?
There isn't enough reliable information on lysine supplements during breastfeeding to say either way. Talk with your doctor or pharmacist about whether it's right for you if you're nursing.
What is L-lysine and why is it in this product?
L-lysine is an amino acid — a building block your body uses to make protein and other important compounds. It's in this product because some evidence suggests it may help with cold sores, and it plays a role in immune and skin health.
Are there any fillers in this capsule?
The capsule itself is made of hypromellose, which is an inactive ingredient that holds the lysine. There are no other fillers or binders added.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if L-Lysine HCL 500 mg is safe with your meds?

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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.

L-Lysine HCL 500 mg label
Go deeper

The Full Monographs Behind L-Lysine HCL 500 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Sources

Sources & How We Checked

L-Lysine HCL 500 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.

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
  1. 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
  2. McCune MA, Perry HO, Muller SA, O'Fallon WM. Treatment of recurrent herpes simplex infections with L-lysine monohydrochloride. Cutis 1984;34:366-73.
  3. DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol 1984;120:48-51. DOI
  4. 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.
  5. 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
  6. 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
  7. 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.

See these in context on the Lysine monograph →

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

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