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Dietary supplement

L-Lysine Ingredients & Drug Interactions

by SuperiorLabs

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

L-Lysine is a dietary supplement by SuperiorLabs 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 by SuperiorLabs

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 your body uses to build and repair tissue. It's also present in many protein-rich foods like meat, cheese, and legumes.

The capsule itself is made from plant cellulose and organic rice concentrate as inactive 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
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 support for immune function and muscle.
  • We looked for evidence on: Herpes labialis (cold sores), Muscle strength, Athletic performance, protein synthesis, collagen formation, wound healing.
  • 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 Athletic performance, Muscle strength.

L-lysine is possibly effective for herpes labialis, also called cold sores — the evidence supports its use for this purpose. For other uses like child growth, pressure ulcers, and diabetic foot ulcers, we don't have enough reliable evidence 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.

L-lysine from food is fine, but the supplement form at high doses may cause stomach upset, including abdominal pain, diarrhea, and indigestion. Long-term safety at supplement doses hasn't been well studied.

For pregnancy, the data on supplement safety isn't established, so talk with your doctor first before taking it. Breastfeeding safety also isn't well documented — 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 a 5-HT4 agonist (a medication for certain digestive issues), check with your doctor or pharmacist before starting this supplement — lysine may reduce its effectiveness. No other medication interactions are documented for the ingredient we hold data on.

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 is a straightforward single-ingredient supplement most commonly used for cold sore prevention or recovery. If you take a 5-HT4 agonist for a gut condition, confirm with your doctor or pharmacist that it won't interfere with your treatment.

At typical doses it's generally well tolerated, though high amounts can upset your stomach. Talk it over with your own healthcare provider to make sure it fits your situation.

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, straight from the product label.

Brand SuperiorLabs
Barcode (UPC) 850569006070
Net contents 120 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Oct 22, 2021
DSLD ID 255999
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 L-Lysine by SuperiorLabs, 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
120
UPC/BARCODE
850569006070
IngredientAmount% DV
L-Lysine500 mg--

Other ingredients: Plant Cellulose, organic Rice concentrate

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.
Formula

Amino acid

L-Lysine capsules manufactured by Superior Labs contain 500 mg pure L-Lysine with absolutely no magnesium stearate, dioxides, preservatives or other potentially harmful artificial ingredients of any kind.

Formulation

100% natural Pure and potent Promotes feelings of well-being Maintain muscle mass Support immune function Support calcium absorption

L-Lysine capsules manufactured by Superior Labs contain 500 mg pure L-Lysine with absolutely no magnesium stearate, dioxides, preservatives or other potentially harmful artificial ingredients of any kind.

This product is formulated, developed and manufactured in a FDA registered and GMP certified facility, 3rd party inspected by a leading compliance authority for superior quality assurance.

Does Not Contain: Magnesium stearate, dioxides, preservatives, or artificial ingredients of any kind.

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

Metal Safe Heavy Metal Tested Made in USA Certified GMP Facility

See for yourself

L-Lysine by SuperiorLabs label

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

What’s inside

The Ingredients in L-Lysine by SuperiorLabs

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 container120 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: Plant Cellulose, Organic Rice concentrate. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Lysine by SuperiorLabs Drug Interactions

Want to check YOUR meds against L-Lysine?

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 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, from the product label.

SuperiorLabs

See all SuperiorLabs products
Name
Superior Labs, LLC.
City
Park City
State
UT
ZipCode
84098
Phone Number
(888) 708-5227
Web Address
www.superiorlabssupplements.com
Pharmacist Counseling Corner

L-Lysine by SuperiorLabs: Common Questions

Does L-Lysine by SuperiorLabs interact with any medications?
Yes. Based on its ingredients, L-Lysine 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 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 says it's possibly effective for herpes labialis — that's cold sores. It's the use this supplement is most studied for, though results vary between people.
What are the side effects?
At typical doses, L-lysine is generally well tolerated. High amounts may cause stomach upset, including abdominal pain, diarrhea, and indigestion. Long-term safety at supplement doses hasn't been thoroughly studied.
Can I take this while pregnant?
Lysine from food is fine, but supplement safety in pregnancy isn't well studied. Talk with your doctor first before taking the supplement form to get personalized advice for your situation.
Is it safe while breastfeeding?
There isn't enough reliable information on supplement safety while breastfeeding. Check with your doctor or pharmacist for guidance on whether it's right for you.
What exactly is L-lysine?
It's an amino acid — one of the building blocks your body uses to make and repair tissue. You get it naturally from protein-rich foods like meat, cheese, and legumes.
Does this product have fillers or other stuff in it?
The capsule is made from plant cellulose and organic rice concentrate. These are the inactive ingredients that hold the L-lysine together.

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

Not sure if L-Lysine 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 label
Sources

Sources & How We Checked

L-Lysine'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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