L-Lysine helps prevent cold sores and boosts immune function, helping cut recurrence and severity of herpes simplex outbreaks, making lysine supplementation easier for busy, health-minded folks.

Available Sizes & Variants:

100 capsules — standard daily dose for maintenance.

Benefits & Features:

• Helps prevent cold sores by delivering 500 mg lysine per capsule.
• May help reduce recurrence and severity of outbreaks in those prone.
• For ongoing prevention, studies have linked daily intakes around 1,000 mg to fewer cold sores, while lower doses may not show the same benefit consistently.
• Great for daily use to support immune function and overall wellbeing.
• Clean capsule formula keeps inactive ingredients low.

Beyond purity, Klaire Labs' approach starts at the source. The brand sticks to certificates of analysis and ingredient verification, with a long standing dedication to cGMP and third party testing. The 500 mg lysine per capsule makes it easy to fit this amino acid into your daily routine. It sits neatly in our supplement store and herbal supplements shelves for easy daily use, helping you find lysine supplements with confidence.

(other) Vegetarian capsule (hydroxypropyl methylcellulose, water), ascorbyl palmitate, and silicon dioxide.

• GTIN: 828054010505
• Manufacturer: Klaire Labs
• Categories: Best SellersCold Sore TreatmentsKlaire LabsLysine SupplementsNew ArrivalsPopular Supplement BrandsSubscribe & Save Products
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Take 1 capsule up to 6 times a day, or as advised by your healthcare provider. Adult -: 6 capsules with food or as directed by a healthcare professional. Children 4 to 14 years - Take up to 3 capsules daily or as directed by a healthcare professional. Children less than 4 years of age - only as directed by a healthcare professional.

Please consult the product packaging for accurate instructions on how to use the product.

The Active Ingredient Is: L-Lysine (Lysine) - L-Lysine hydrochloride

L-Lysine is an essential amino acid that plays a vital role in building body proteins and supporting tissue growth and repair.

This form is pharmaceutical-grade L-lysine hydrochloride, supplied as a single-ingredient supplement with minimal excipients for encapsulation.

What Does L-Lysine Do?

L-Lysine aids in protein synthesis and is involved in normal immune function and tissue repair.

This nutrient supports routine physiological processes and, in research contexts, has been associated with reduced recurrence and perceived severity of cold sore outbreaks in susceptible individuals, alongside broader roles in growth and calcium utilisation.

This supplement is not intended to diagnose, treat, cure, or prevent any disease.

Klaire Labs has a long-standing track record in the supplement industry, recognised for adhering to current good manufacturing practices (cGMP) and a robust quality control framework. This heritage of quality, including in-house and third-party testing for purity and potency, sets Klaire Labs apart as a trusted partner for Welzo.

The brand's quality ethos is further demonstrated by their rigorous raw material verification, finished product analysis and contaminant screening. Their commitment to ingredient sourcing and transparency, with COAs from vetted suppliers and dedicated incoming material checks, aligns with Welzo's standards for trust and safety. Our evaluation emphasised Klaire Labs' emphasis on traceability and ethical sourcing as core strengths in a premium category.

For L-Lysine, Klaire Labs offers a product that complements their quality-centric approach, making it a natural fit for Welzo customers seeking a single-ingredient, well-controlled lysine supplement. This brand aligns with our expert-led selection framework, and we confidently recommend Klaire Labs as a trusted supplier. This brand was evaluated by our team of medical experts for compliance with our quality certification process.