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Dietary supplement

L-Lysine Viraguard 500 mg Ingredients & Drug Interactions

by Vitamin World

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

L-Lysine Viraguard 500 mg is a dietary supplement by Vitamin World 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 Viraguard 500 mg by Vitamin World

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, an amino acid, at 500 mg per capsule. The capsule itself is made from gelatin.

There are no other active ingredients.

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

This product doesn't appear to be marketed for a specific use, so we graded Lysine's overall clinical evidence instead.

Moderate

Some clinical evidence supports Lysine for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Herpes labialis (cold sores) — rated "Possibly Effective" (Natural Medicines).

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

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 higher amounts, it may cause stomach upset including abdominal pain, diarrhea, and indigestion.

Long-term safety at high doses hasn't been well studied. Supplement use of lysine in pregnancy and breastfeeding hasn't been well studied, so there isn't enough data to know either way.

Talk with your doctor or pharmacist for personalized advice if you're pregnant, planning pregnancy, 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.

If you take a 5-HT4 agonist, double-check with your doctor or pharmacist before starting this product—lysine may reduce how well it works.

Check your own medication Run your meds through the checker above

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 may help with cold sores if you're looking for a natural option. If you take a 5-HT4 agonist, confirm with your doctor or pharmacist first.

At normal doses it's well tolerated, though high amounts can cause digestive upset. Check with your own doctor or pharmacist before starting, especially if you're pregnant, breastfeeding, or on other medications.

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 May 24, 2013.

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 Viraguard 500 mg, straight from the product label.

Brand Vitamin World
Barcode (UPC) 766443128069
Net contents 100 Rapid Release Capsule(s)
Market status On market
Date entered into DSLD May 24, 2013
DSLD ID 21256
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) 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 Viraguard 500 mg by Vitamin World, 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)
UPC/BARCODE
766443128069
IngredientAmount% DV
L-Lysine500 mg--

Other ingredients: Gelatin, 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.
Storage

Store at room temperature.

General Statements

From the moment raw ingredients reach our facilities to the time a finished supplement is packaged, stringent analysis confirms the potency, purity and nutritional content of every nutritional product that bears the Vitamin World name. We guarantee it!

Amino Support Formula

Lysine is an indispensable amino acid that cannot be made by the body. Amino acids form the basis for protein, which helps construct and maintain the critical structures in the body.* Lysine is also used for the health and integrity of skin.*

Get healthy. Free form

Seals/Symbols

QA QUALITY ASSURED

Formulation

No Artificial Color, 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

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

Keep out of reach of children.

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

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

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.

Brand IP Statement(s)

(C)2012 Vitamin World, Inc.

General

PROD. #12806 B12805 05C

FDA Statement of Identity

AMINO ACID SUPPLEMENT

Suggested/Recommended/Usage/Directions

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

See for yourself

L-Lysine Viraguard 500 mg by Vitamin World label

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

What’s inside

The Ingredients in L-Lysine Viraguard 500 mg by Vitamin World

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

Serving size1 Capsule(s) Dosage formCapsule 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: Gelatin, Contains <2% of. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Lysine Viraguard 500 mg by Vitamin World Drug Interactions

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

Vitamin World

See all Vitamin World products
Phone Number
1-800-228-4533
Web Address
www.vitaminworld.com
Pharmacist Counseling Corner

L-Lysine Viraguard 500 mg by Vitamin World: Common Questions

Does L-Lysine Viraguard 500 mg by Vitamin World interact with any medications?
Yes. Based on its ingredients, L-Lysine Viraguard 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 Viraguard 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 help cold sores?
Yes, possibly. The evidence we have rates it as possibly effective for cold sores (herpes labialis). That means there's some evidence it can help, but it's not a guaranteed cure—talk with your doctor if you want to know if it's right for you.
What are the side effects I should watch for?
At typical doses, lysine is generally well tolerated. At higher amounts, some people experience stomach upset including abdominal pain, diarrhea, and indigestion. Long-term safety at high doses isn't well studied, so stick to the label dose.
Is it safe to take while pregnant or breastfeeding?
There isn't enough data on supplement lysine in pregnancy or breastfeeding to know either way. Lysine from food is fine, but check with your doctor first before taking a supplement. They can give you personalized advice based on your situation.
Does this help with other conditions besides cold sores?
The evidence we hold doesn't establish lysine's effectiveness for child growth, pressure ulcers, or diabetic foot ulcers. Cold sores are the only use we have evidence for.
What's in the capsule besides lysine?
The capsule is made of gelatin. There are no other active ingredients—just the 500 mg of L-lysine you're taking it for.

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

Not sure if L-Lysine Viraguard 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 Viraguard 500 mg label
Go deeper

The Full Monographs Behind L-Lysine Viraguard 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 Viraguard 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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