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Amino Acid

L-Lysine

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L-Lysine. Essential amino acid for collagen and HSV prevention.

How it works. Antagonizes arginine for HSV replication.

What the research supports. 1 graded claims. Strongest: Reduces HSV recurrence (moderate).

How much to take. Typical dose: 1000 mg/d.

Side effects and interactions. 1 medication interaction listed. No serious side effects listed at normal doses.

Stacking. Pairs well with Vitamin D3 + K2, Zinc, Collagen peptides.

Common forms. Available as Free-form crystalline powder, Capsules or tablets, Pre-mixed recovery or hydration beverages, Time-release formulations.

Key studies. 8 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried L-Lysine. Anecdotes are not medical advice.

L-Lysine. Essential amino acid for collagen and HSV prevention.

Molecular structureC6H14N2O2 · 146.19 g/mol

What it is

Essential amino acid for collagen and HSV prevention.

Food sources

Dietary protein from animal sources (meat, fish, eggs, dairy) and plant sources (soy, legumes, grains)Free-form amino acid powders and capsulesTargeted pre-workout, recovery, or sleep formulations

Goals

Immune FunctionSkin, Hair & Nails

How it works

Antagonizes arginine for HSV replication.

Pathways

  • Antagonizes arginine for HSV replication

Effects

  • ↓HSV recurrence decreases

What the research supports

Reduces HSV recurrencemoderate

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
1000 mg/d
TimingConsistent daily timing recommended; split larger doses if GI tolerance is a concern.
With foodEither with or without food.
Best formMost evidence is based on the free-form crystalline powder form.
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Side effects & interactions

Common side effects

  • GI upset

Medication interactions

Prescription medications (general)minor

Always disclose L-Lysine use to your prescriber — additive, antagonistic, or pharmacokinetic interactions are possible.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

  • Vitamin D3 + K2Foundational immune modulation.
  • ZincRequired cofactor for innate and adaptive immune function.
  • Collagen peptidesProvides amino acid substrate for connective tissue synthesis.

Common forms

  • Free-form crystalline powder
  • Capsules or tablets
  • Pre-mixed recovery or hydration beverages
  • Time-release formulations

Key studies

8 studies cited in total.

PubMed: L-Lysine — Reduces HSV recurrence ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching L-Lysine and "Reduces HSV recurrence". Filter by RCT, meta-analysis, or year on the results page.

PubMed: L-Lysine — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching L-Lysine and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

PubMed: L-Lysine — meta-analysis ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching L-Lysine and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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