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Dietary supplement

L-Lysine 500 mg Ingredients & Drug Interactions

by Nature's Bounty

Tablet Or Pill Category: Amino Acid/protein
Most serious interaction: Minor
The interaction bottom line Most serious interaction: Minor

L-Lysine 500 mg is a dietary supplement by Nature's Bounty 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.

HelloPharmacist Scorecard of L-Lysine 500 mg by Nature's Bounty

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 1 active ingredient: L-lysine, an amino acid your body uses to support immune function and wound healing. It also contains vegetable cellulose as an inactive ingredient (the capsule material).

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: supports immune system function and skin health.
  • We looked for evidence on: Herpes labialis (cold sores), Genital herpes, Oral ulcers.
  • The strongest evidence on file: Lysine is rated "Possibly Effective" for Herpes labialis (cold sores) (Natural Medicines).

The evidence supports L-lysine as possibly effective for herpes labialis, commonly called cold sores. For other uses in the product facts—child growth, pressure ulcers, and diabetic foot ulcers—we don't have enough reliable evidence to establish whether it works.

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.

L-lysine is generally well tolerated at typical doses. At high amounts, some people experience stomach upset, abdominal pain, diarrhea, or indigestion.

Long-term safety hasn't been thoroughly studied. The safety of L-lysine supplements in pregnancy and breastfeeding hasn't been well studied, so check with your doctor or pharmacist before taking it if you're pregnant or breastfeeding—food sources of lysine are fine.

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.

Before taking this product, check with your doctor or pharmacist if you take any 5-HT4 agonists (medications that help move food through your stomach). L-lysine may reduce how well these drugs work.

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 500 mg is worth considering if you're looking for support with cold sores, where the evidence suggests it may help. If you're pregnant, breastfeeding, or take any medications—especially for stomach function—talk it over with your doctor or pharmacist before you start.

They can check your specific situation and confirm it's the right choice for you.

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 Jul 25, 2014.

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 500 mg, straight from the product label.

Brand Nature's Bounty
Barcode (UPC) 074312030604
Net contents 100 Tablet(s)
Market status On market
Date entered into DSLD Jul 25, 2014
DSLD ID 35623
Product type Amino Acid/protein
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), 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 500 mg by Nature's Bounty, 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 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
UPC/BARCODE
074312030604
IngredientAmount% DV
L-Lysine500 mg--

Other ingredients: Vegetable Cellulose, Contains <2% of

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.
Seals/Symbols

LABORATORY TESTED GUARANTEED QUALITY

General

Prod. No. 3060 10F B3060

General Statements

Supports Immune System Function

COATED FOR EASY SWALLOWING

Use for the Health and Integrity of Skin & Lips

Lysine is an indispensable amino acid that cannot be made by the body. Amino acids perform a variety of functions and form the basis for protein. Lysine is also used for the health and integrity of skin.

Mon. - Sat. 9 AM - 7 PM ET

FDA Statement of Identity

AMINO ACID SUPPLEMENT

Suggested/Recommended/Usage/Directions

DIRECTIONS: For adults, take one (1) tablet two times daily, preferably on an empty stomach.

Formulation

Suitable for Vegetarians

No Artificial Flavor or Sweetener, No Preservatives, No Sugar, No Starch, No Milk, No Lactose, No Soy, No Gluten, No Wheat, No Yeast, No Fish. Sodium Free.

Precautions

WARNING: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.

Discontinue use and consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Do not use if seal under cap is broken or missing.

Storage

Store at room temperature.

Brand IP Statement(s)

(C) 2014 Nature's Bounty, Inc.

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.

See for yourself

L-Lysine 500 mg by Nature's Bounty label

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

What’s inside

The Ingredients in L-Lysine 500 mg by Nature's Bounty

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.

L-Lysine

Interacts with
1 drug
500 mg per serving Form: L-Lysine Hydrochloride

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 & interactions

Other (inactive) ingredients: Vegetable Cellulose, Contains <2% of. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Lysine 500 mg by Nature's Bounty Drug Interactions

Want to check YOUR meds against L-Lysine 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 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-Lysine1 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 500 mg, from the product label.

Pharmacist Counseling Corner

L-Lysine 500 mg by Nature's Bounty: Common Questions

Does L-Lysine 500 mg by Nature's Bounty interact with any medications?
Yes. Based on its ingredients, L-Lysine 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 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 actually work for cold sores?
The evidence suggests L-lysine is possibly effective for cold sores. Results vary from person to person, and you may need to try it for a while to see whether it helps you.
What side effects should I watch for?
Most people tolerate it well. The most common side effects are stomach upset, abdominal pain, diarrhea, and indigestion, especially at higher doses. If any of these bother you, try lowering your dose or stopping.
Is it safe to take while I'm pregnant or breastfeeding?
The safety of L-lysine supplements during pregnancy and breastfeeding hasn't been well studied. Lysine from food is fine, but if you're thinking about taking a supplement, check with your doctor first so they can weigh your individual situation.
Can I take this long-term?
L-lysine is generally well tolerated at typical doses, but long-term safety hasn't been thoroughly studied. If you're planning to use it regularly over time, talk to your doctor or pharmacist about what makes sense for you.

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

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

Our pharmacists answer your medication & supplement questions — free.

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 500 mg label
Go deeper

The Full Monographs Behind L-Lysine 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 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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