Lysine 400 Ingredients & Drug Interactions
What is this page for?
First and foremost: checking Lysine 400 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
Lysine 400 is a dietary supplement by ProCaps Laboratories 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.
Check Your Meds Against Lysine 400 by ProCaps Laboratories
Ask about any prescription or over-the-counter medication and we check it for interactions with Lysine 400 by ProCaps Laboratories — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Lysine 400 by ProCaps Laboratories
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.
What’s inside
Full disclosure
Lysine 400 contains a single active ingredient: L-lysine, an amino acid your body uses to build protein and support various functions. Each capsule delivers 400 mg of this amino acid.
The supplement is packaged in a gelatin capsule as the inactive ingredient.
Does it work?
Moderate evidence
L-lysine is possibly effective for herpes labialis (cold sores) based on the evidence we hold. For other uses — child growth, pressure ulcers, and diabetic foot ulcers — the evidence isn't established well enough to rate it one way or the other.
How safe is it?
Well-documented data
L-lysine from food is safe, but when taken as a supplement, the safety picture is less clear. At typical doses, it's generally well tolerated; however, high amounts may cause stomach upset, and long-term safety hasn't been well studied.
The most common side effects reported are abdominal pain, diarrhea, and indigestion. There's one case report of oral lysine associated with kidney inflammation that progressed to chronic kidney failure, though this is rare.
For pregnancy, supplement safety isn't well studied, so talk with your doctor first before taking it. There isn't enough reliable information on lysine supplements while breastfeeding either, so caution is advised — check with your healthcare provider.
Meds to double-check
Minor interactions only
If you take a 5-HT4 agonist (a medication for certain digestive disorders), check with your pharmacist before starting this product — lysine may reduce its effectiveness.
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 400 may help with cold sores if you're looking for a possibly effective option. If you take a 5-HT4 agonist for a digestive condition, check with your pharmacist first.
At standard doses it's generally well tolerated, but high amounts can upset your stomach. Talk to your pharmacist about whether this supplement fits your health picture.
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 24, 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
General information
Key facts about Lysine 400, straight from the product label.
| Brand | ProCaps Laboratories |
|---|---|
| Barcode (UPC) | 141232 |
| Net contents | 360 Easy-To-Swallow Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Oct 24, 2022 |
| DSLD ID | 275266 |
| Product type | Amino Acid/protein |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 400 by ProCaps Laboratories, sourced from the NIH Dietary Supplement Label Database.
Tap any ingredient to jump to its full detail below.
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 Consume one or more capsules daily or as recommended by your physician. As with any dietary supplement, this product is most effective as part of a healthy diet and active lifestyle, along with a daily multi-vitamin-mineral formula. For questions about the use of this product call 800.332.7799.
General Statements
www.HSN.com 800.944.9999 www.QVC.com 800.345.1515 Questions? 800.800.1200 www.ProCapslabs.com
All-solar manufacturing
Brand IP Statement(s)
Copyright 2021 ProCaps Labs
Formula
400 mg lysine Free form amino acid
Andrew Lessman’s Lysine 400 is a pure, natural source of the essential amino acid l-lysine. Lysine has become a very popular supplement, because of its role in supporting the immune system, as well as its central role in fat burning and energy metabolism. Lysine is one of nine amino acids referred to as “essential” because it cannot be produced by the body. Lysine is vital for the growth and development of body tissues and also plays a critical role in the body's production of energy, since it is a precursor to acetyl CoA, a critical component of all energy metabolism. Additionally, lysine is also a precursor to carnitine, which is essential for all fat metabolism. Lysine also plays an important structural role in the formation of collagen, a vital component of healthy skin, bones, joints and connective tissue (tendons, ligaments and cartilage). Lysine also plays a role in helping the body manage calcium. In short, lysine plays a multitude of critical roles in the most vital systems in our body.
FDA Statement of Identity
Dietary Supplement
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.
Formulation
Contains no milk, soy, yeast, corn, wheat, gluten, sodium, salt, sugar, fat, cholesterol, color, preservative, common allergens or manufacturing additives. Contains no additives of any kind.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Lysine 400 by ProCaps Laboratories label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Lysine 400 by ProCaps Laboratories
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 container360 Amounts shown are per serving.
L-Lysine
Interacts with1 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 t...
L-Lysine monograph & interactionsOther (inactive) ingredients: Gelatin Capsule. These complete the product’s ingredient list but are not active constituents.
Lysine 400 by ProCaps Laboratories Drug Interactions
HelloPharmacist Interaction Report
Lysine 400 by ProCaps Laboratories contains one ingredient — L-lysine — that has a documented interaction with a specific drug type.
L-lysine may reduce how well 5-HT4 agonists (medications that work on a particular serotonin pathway in your gut) perform. The effect is Minor in severity; animal research suggests lysine acts as a partial antagonist to these drugs and may blunt their ability to work.
Read the full breakdown — every affected drug type, severity by severity
Altogether, these interactions span 1 individual medication.
If you take a 5-HT4 agonist — typically prescribed for certain types of digestive disorders — check with your pharmacist or doctor before starting this supplement. They can advise whether the interaction matters for your situation or whether you need to adjust timing or dosing.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Lysine 400?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Lysine 400 interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in Lysine 400 interact with drugs. Each result below shows which ingredient is responsible. L-Lysine
TegaserodZelnorm
How Tegaserod interacts with Lysine 400 — through 1 ingredient. Tap an ingredient for the detail:
L-lysine5-ht4 Agonists Minor
Interaction Summary
Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Read the full L-lysine + Tegaserod interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Lysine 400 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-Lysine
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.
Brand information
Manufacturer and brand details for Lysine 400, from the product label.
ProCaps Laboratories
See all ProCaps Laboratories products- Name
- ProCaps Laboratories
- City
- Henderson
- State
- NV
- ZipCode
- 89011
- Phone Number
- 800.800.1200
- Web Address
- www.ProCapsLabs.com
Lysine 400 by ProCaps Laboratories: Common Questions
Does Lysine 400 by ProCaps Laboratories interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will lysine help with my cold sores?
What side effects should I watch for?
Is it safe to take while pregnant?
Can I take it while breastfeeding?
Does lysine work for pressure ulcers or diabetic foot ulcers?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Lysine 400 is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Lysine 400’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Lysine 400'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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
- 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
- McCune MA, Perry HO, Muller SA, O'Fallon WM. Treatment of recurrent herpes simplex infections with L-lysine monohydrochloride. Cutis 1984;34:366-73.
- DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol 1984;120:48-51. DOI
- 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.
- 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
- 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
- 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.
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