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Dietary supplement

Lysine 475 mg Ingredients & Drug Interactions

by Dr. Clark Store

Lysine 475 mg label
See full label image
Capsule Category: Amino Acid/protein
Most serious interaction: Minor
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Lysine 475 mg 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

The interaction bottom line Most serious interaction: Minor

Lysine 475 mg is a dietary supplement by Dr. Clark Store 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.

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Check Your Meds Against Lysine 475 mg by Dr. Clark Store

Ask about any prescription or over-the-counter medication and we check it for interactions with Lysine 475 mg by Dr. Clark Store — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Lysine 475 mg by Dr. Clark Store

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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

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 at 475 mg per capsule. Lysine is an amino acid — one of the building blocks your body uses to make and repair proteins.

The capsule itself is gelatin.

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: Essential amino acid for protein and collagen formation.
  • We looked for evidence on: Herpes labialis (cold sores), Child growth, Muscle strength, Calcium absorption, Connective tissue health.
  • The strongest evidence on file: Lysine is rated "Possibly Effective" for Herpes labialis (cold sores) (Natural Medicines).
  • Also on file: Lysine is rated "Insufficient Reliable Evidence To Rate" for Muscle strength, Child growth.

Lysine is possibly effective for cold sores (herpes labialis) — the research suggests it may help, though the evidence isn't airtight. For other uses listed in the literature — child growth, pressure ulcers, and diabetic foot ulcers — there isn't enough reliable evidence yet to say 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.

Lysine is generally well tolerated at typical doses. High amounts may cause stomach upset, including abdominal pain, diarrhea, and indigestion.

Long-term safety with supplements hasn't been thoroughly studied. There's one case report of very high doses causing kidney inflammation, though this is rare.

Supplement lysine safety in pregnancy hasn't been well studied — lysine from food is fine, but if you're pregnant, check with your doctor before taking a supplement. There isn't enough data on breastfeeding either, so talk with your doctor or pharmacist first if you're nursing.

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.

Check your medications against 5-HT4 agonists before taking this product — lysine may reduce how well they work. For any other drugs you take, use the search tool on this page to be sure.

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.

Lysine may help with cold sores if the evidence holds up for you. It's generally well tolerated, but high doses can upset your stomach.

If you're pregnant or breastfeeding, or on any medications, check with your pharmacist before starting — especially if you take a 5-HT4 agonist.

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 22, 2020.

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 Lysine 475 mg, straight from the product label.

Brand Dr. Clark Store
Barcode (UPC) 652384105637
Net contents 100 Capsule(s)
Market status On market
Date entered into DSLD May 22, 2020
DSLD ID 219980
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 Lysine 475 mg by Dr. Clark Store, 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
UPC/BARCODE
652384105637
IngredientAmount% DV
L-Lysine475 mg--

Other ingredients: Gelatin 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.
Suggested/Recommended/Usage/Directions

Suggested Use: Take 1 capsule, or as directed by a healthcare professional.

General Statements

Self Health Resource Center 1055 Bay Blvd., Ste A Chula Vista, CA 91911 Customer Service Toll Free: (866) DR-CLARK (372-5275) www.DrClarkStore.com

Leader in purity Established by Dr. Clark's family in 1993

Company does not adopt any Dr. Clark claims.

Formulation

Our products don't contain flow agents like magnesium stearate. Not now, not ever.

Seals/Symbols

Made in USA

GMP Quality Assured

Formula

Essential amino acid

FDA Statement of Identity

Dietary Supplement

Storage

Store at room temperature.

Precautions

Keep away from children.

Warning: If you are pregnant, nursing or taking any medications, consult your doctor before use.

If any adverse reactions occur, immediately stop using this product and consult your doctor. If seal under cap is damaged or missing, do not use.

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.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Lysine 475 mg by Dr. Clark Store label

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

Lysine 475 mg label

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)
What’s inside

The Ingredients in Lysine 475 mg by Dr. Clark Store

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

Interacts with
1 drug
475 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 Capsules. These complete the product’s ingredient list but are not active constituents.

Interaction report

Lysine 475 mg by Dr. Clark Store Drug Interactions

Want to check YOUR meds against Lysine 475 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

L-Lysine 1

Individual Drug Interactions

The ingredients in Lysine 475 mg interact with 1 drug. Click any drug to see the details.

1 of the 1 ingredient in Lysine 475 mg interact with drugs. Each result below shows which ingredient is responsible. L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Lysine 475 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
L-Lysine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Lysine 475 mg, from the product label.

Dr. Clark Store

See all Dr. Clark Store products
Name
Dr. Clark Store
Street Address
1055 Bay Blvd., Ste A
City
Chula Vista
State
CA
ZipCode
91911
Phone Number
(866) 372-5275
Web Address
www.DrClarkStore.com
Pharmacist Counseling Corner

Lysine 475 mg by Dr. Clark Store: Common Questions

Does Lysine 475 mg by Dr. Clark Store interact with any medications?
Yes. Based on its ingredients, Lysine 475 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?
Lysine 475 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 lysine actually help with cold sores?
The evidence suggests it may — we rate it possibly effective for cold sores. That means research points toward benefit, but it's not ironclad yet. You may see results, or you may not; individual responses vary.
What are the most common side effects?
At normal doses, lysine is well tolerated. Higher amounts can cause stomach upset — abdominal pain, diarrhea, or indigestion. If that happens, lower your dose or stop and talk to us.
Is it safe to take if I'm pregnant?
There isn't enough data on supplement lysine safety in pregnancy. Lysine from food is fine, but before taking a supplement, check with your doctor — they know your full health picture and can give you personalized advice.
Can I take this while breastfeeding?
There isn't enough reliable information on supplement lysine while breastfeeding. Talk with your doctor or pharmacist first to make sure it's right for you.
Will lysine interact with my medications?
One documented interaction: lysine may reduce the effects of 5-HT4 agonists (a serotonin-based drug). Check your exact medications with the search tool on this page — that's the quickest way to know for sure.

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

Not sure if Lysine 475 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.

Lysine 475 mg label
Go deeper

The Full Monographs Behind Lysine 475 mg’s Ingredients

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

Herb & supplement monograph

Lysine

Interacts with 1 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 try to prevent or shorten cold sores, but...

Read the full Lysine monograph →
Sources

Sources & How We Checked

Lysine 475 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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