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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, an amino acid your body uses to build and repair proteins. The capsule itself is made from hypromellose, an inactive ingredient that helps hold the supplement together.

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: Herpes labialis and cold sore support.
  • We looked for evidence on: Herpes labialis (cold sores), Genital herpes, Viral infection recovery.
  • 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) — the evidence suggests it may help, though it's not ironclad. For child growth, pressure ulcers, and diabetic foot ulcers, the evidence on file isn't strong enough to say either way.

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.

At normal doses, L-lysine is generally well tolerated. High amounts may trigger stomach upset, and long-term safety data is limited.

Some people report abdominal pain, diarrhea, or indigestion. There's one isolated case report of a person who developed kidney inflammation linked to oral lysine, though this is very rare.

During pregnancy, food sources of lysine are fine, but supplement safety hasn't been well studied — talk with your doctor before taking it. While breastfeeding, there isn't enough reliable data to know if supplemental lysine is safe, so check with your doctor or pharmacist first.

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 a 5-HT4 agonist, lysine may reduce how well it works — check with your doctor or pharmacist before adding this supplement. No other medication categories show documented interactions with 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 if you want to try it, and it's generally well tolerated at typical doses. If you take any medications, especially 5-HT4 agonists or anything else for digestion or motility, confirm with your doctor or pharmacist before starting.

Pregnant or breastfeeding people should talk it over with their 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 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 300 Vegetarian Capsules
Market status On market
Date entered into DSLD Oct 22, 2021
DSLD ID 254583
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
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
300
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!

Formulation

Free of: Sugar, soy, dairy, yeast, gluten or additives

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, take 1 capsule 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 container300 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 Rd
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.
Does L-lysine really work for cold sores?
The evidence says it's possibly effective — meaning some research supports it, but it's not proven beyond doubt. If you want to try it for that purpose, it's worth a shot, especially since it's generally well tolerated.
What side effects should I watch for?
Most people have no problems, but some report stomach pain, diarrhea, or indigestion — especially at higher doses. Long-term safety data is sparse, so don't take huge amounts without talking to your doctor first.
Is it safe to take while pregnant or breastfeeding?
Lysine from food is fine, but supplement safety during pregnancy and breastfeeding hasn't been well studied. Talk with your doctor or pharmacist before taking this supplement if you're pregnant or nursing.
What is L-lysine and why is it in this product?
L-lysine is an amino acid — one of the building blocks your body uses to make and repair proteins. It's in this supplement because evidence suggests it may help with cold sores.
Can I take this if I have kidney problems?
There's one rare case report linking high-dose oral lysine to kidney inflammation, so if you have any kidney condition, discuss this supplement with your doctor first before taking it.

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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Ask a pharmacist

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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