L-Lysine
Amino Acid
Also known as: Lysine, L-Lysine HCl, Lysine Monohydrochloride
B
Grade B💊 500-3000 mg daily🎯 4 primary uses🔗 3 synergies✅ Generally safe
Levels upFitness+50 pts
Overview
Essential amino acid important for protein synthesis, collagen formation, calcium absorption, and immune function, particularly noted for antiviral properties.
Primary Uses
Cold sore preventionProtein synthesisCollagen supportCalcium absorption
Frequently Asked About L-Lysine
How much L-Lysine should I take?
The typical effective range is 500-3000 mg daily. Individual needs vary based on age, body weight, diet, and goals — start at the lower end and adjust based on response. Always consult a healthcare provider before starting a new supplement.
When is the best time to take L-Lysine?
Between meals or with meals. Consistency matters more than perfect timing — pick a daily anchor (e.g. with breakfast or before bed) and stick with it.
Should I take L-Lysine with food?
Either way.
Does L-Lysine interact with medications?
Yes — known interactions include May interact with aminoglycoside antibiotics. If you take any prescription medication, talk to your doctor or pharmacist before starting L-Lysine.
What does L-Lysine pair well with?
L-Lysine stacks well with Vitamin C, Zinc, and Proline — these combinations either improve absorption or work synergistically toward common goals.
What are the side effects of L-Lysine?
Most people tolerate L-Lysine well. The most commonly reported side effects are GI upset at high doses. Side effects are usually dose-dependent — lowering the dose often resolves them.
Dosage
Typical range
500-3000 mg daily
Timing
Between meals or with meals
With food
Either way
Duration
Safe for long-term use
Special Populations
Those prone to cold sores
Research & Studies
Search the literature now
We haven’t curated landmark studies for L-Lysineyet — one-click into the primary literature here. PubMed (RCTs) is usually the highest-signal starting point.
Mechanism of Action
- • Competes with arginine for viral replication
- • Essential for collagen synthesis
- • Supports carnitine production
Evidence Quality
Evidence Grade B
Good evidence for cold sore prevention, protein synthesis
Safety & Contraindications
Common Side Effects
- • GI upset at high doses
Pregnancy & Breastfeeding
Consult healthcare provider
Liver & Kidney Notes
Caution with kidney disease at high doses
Interactions
💊 Medications
- • May interact with aminoglycoside antibiotics
🧪 Supplements
- • Balance with arginine
Stacking & Synergies
Pairs Well With
Avoid Combining With
High arginine during outbreak
Best Goal Synergies
Immune supportCollagen synthesis
Buying Guide
What to Look For
- • L-lysine not D-lysine
- • Free form or HCl
Standardization Markers
L-form specified
Adulteration risk
Low
Practical Notes
- • Higher doses during cold sore outbreaks
- • Maintain lysine:arginine balance
Tags
amino acidessentialantiviralcollagen
More in Amino Acid
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Hydrolyzed Whey Protein
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L Carnitine
L-carnitine is a naturally occurring compound synthesized from amino acids that plays a crucial role in transporting long-chain fatty acids into mitochondria for energy production. Evidence supports modest benefits for exercise performance and recovery in carnitine-deficient individuals, though benefits in healthy populations are limited.
Last reviewed: June 2026 by the Formulate Research Team. Sources cited above; methodology and scoring criteria published here.
Cite this page
Formulate Research Team. (2026, June). L-Lysine — Evidence-Based Supplement Guide. Formulate Supplement Encyclopedia. https://app.formulate-health.app/learning/supplements/l-lysine-supplement
Educational content based on published research and our scoring methodology. Not medical advice — consult a qualified healthcare provider before starting, stopping, or changing supplements, especially if you take medications, are pregnant, or have a medical condition.