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Dietary supplement

L-Lysine 500 mg Ingredients & Drug Interactions

by Metabolic Maintenance

Capsule 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 Metabolic Maintenance 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 Metabolic Maintenance

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.
  • “L-Lysine” is listed as a grouped ingredient — the label gives one combined amount (500 mg) without saying how much of each component you get.

This product contains one active ingredient: L-lysine hydrochloride, an amino acid your body uses in protein structure and immune function. The capsule itself is vegetarian cellulose, an inert material that holds the ingredient 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

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). For other uses like child growth, pressure ulcers, and diabetic foot ulcers, there isn't enough reliable evidence in our data to know 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. The most common side effects from oral use are abdominal pain, diarrhea, and indigestion.

High amounts may cause stomach upset, and long-term safety hasn't been thoroughly studied. Because supplement safety in pregnancy is not well studied, check with your doctor before taking it if you're pregnant.

There isn't enough reliable information on its use while breastfeeding, so caution is advised — talk it over with your doctor or pharmacist.

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 conditions), check with your doctor or pharmacist before adding this supplement — lysine may theoretically reduce its effectiveness.

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.

If you're dealing with cold sores, L-lysine may be worth trying based on current evidence. If you take a 5-HT4 agonist for digestive issues, confirm with your doctor or pharmacist before starting.

Most people tolerate it well at standard doses, though some experience stomach upset. Run through your medications with your own healthcare provider to make sure it's right 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 Sep 22, 2022.

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 Metabolic Maintenance
Barcode (UPC) 838287001362
Net contents 100 Capsule(s)
Market status On market
Date entered into DSLD Sep 22, 2022
DSLD ID 274057
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), 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 500 mg by Metabolic Maintenance, 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:
4 Capsule(s)
Servings per container
100
UPC/BARCODE
838287001362
IngredientAmount% DV
L-Lysine Hydrochloride625 mg--
L-Lysine500 mg--

Other ingredients: Vegetarian Cellulose Capsule

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.
Precautions

Caution: Pregnant or lactating women, consult your healthcare professional before taking this product.

Keep tightly closed in a cool, dry place, out of the reach of children.

Storage

Keep tightly closed in a cool, dry place, out of the reach of children.

Formulation

Egg free Gluten free Free of nuts Dairy free

Manufactured in a GMP Compliant Facility

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions: One to four (1-4) capsules daily, or as directed by a healthcare professional. Best taken between meals.

See for yourself

L-Lysine 500 mg by Metabolic Maintenance 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 Metabolic Maintenance

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
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 monograph & interactions

Other (inactive) ingredients: Vegetarian Cellulose Capsule. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Lysine 500 mg by Metabolic Maintenance 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.

Metabolic Maintenance

See all Metabolic Maintenance products
Name
Metabolic Maintenance
Street Address
601 N Larch Street
City
Sisters
State
Oregon
ZipCode
97759
Phone Number
800-772-7873
Web Address
MetabolicMaintenance.com
Pharmacist Counseling Corner

L-Lysine 500 mg by Metabolic Maintenance: Common Questions

Does L-Lysine 500 mg by Metabolic Maintenance 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?
It's possibly effective for cold sores, which means the research is encouraging but not yet definitive. Many people find it helpful, though results vary.
What are the side effects I should watch for?
Most common are abdominal pain, diarrhea, and indigestion. High doses are more likely to cause stomach upset. One very rare case linked long-term use to kidney problems, but this is extremely uncommon.
Can I take this if I'm pregnant or breastfeeding?
Supplement safety in pregnancy and breastfeeding hasn't been well studied. Talk with your doctor first — lysine from food is fine, but they can advise whether a supplement makes sense for you right now.
Is L-lysine the same as lysine from food?
It's the same amino acid, but food sources haven't raised safety concerns. Supplement safety over the long term is less well studied, so talk with your doctor if you're thinking about taking high-dose supplements regularly.
What does L-lysine do in my body?
Lysine is an amino acid your body uses to build proteins and support immune function. It plays a role in collagen formation and tissue repair.

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

Not sure if L-Lysine 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 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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