Enhanced immune function
Supports immune system and antiviral activity
L-Lysine
Essential amino acid crucial for collagen synthesis, immune function, and calcium absorption
Scientific nameL-Lysine
FormulaC6H14N2O2
Molecular weight146.19 g/mol
CAS56-87-1
90
absorption score
8
safety / 10
15
USD per month
5
documented interactions
Check it against something
L-Lysine with:
- Amylase
- Ashwagandha
- Avocado Oil
- BCAA (Branched-Chain Amino Acids)
- Beetroot Powder
- Beta-Alanine
- Bifidobacterium lactis
- Bifidobacterium longum
- Bovine Collagen
- Caffeine
- Calcium
- Calcium Bone Formula
- Calcium Carbonate
- Casein Protein
- Chicken Collagen
- Choline (Bitartrate)
- Chondroitin Sulfate
- Coconut Oil
- Collagen Peptides
- Comprehensive Immune Support Complex
- Comprehensive Multivitamin-Mineral Complex
- Creatine HCL
- Creatine Monohydrate
- D-Mannose
- DHA
- Electrolyte Blend
- EPA
- Fish Oil (EPA/DHA)
- Folate (5-MTHF)
- Ginger
- Iron Fumarate
- Iron Sulfate
- Joint Mobility Formula
- Keratin
- Krill Oil
- L-Carnitine
- L-Citrulline
- Lactase
- Lactobacillus acidophilus
- Lactobacillus rhamnosus
- Lipase
- Magnesium Citrate
- Magnesium Glycinate
- Magnesium Oxide
- Marine Collagen
- Melatonin
- Modafinil
- Olive Oil Extract
- Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula
- Papain
- Protease
- Saccharomyces boulardii
- Turmeric
- Vitamin B12 (Cyanocobalamin)
- Vitamin B12 (Methylcobalamin)
- Vitamin C (Ascorbic Acid)
- Vitamin C (Sodium Ascorbate)
- Vitamin D3
- Whey Protein
- Zinc Gluconate
Nothing found
82
out of 100
Works better together
Compatible. Timing differs, so follow each supplement's own window.
What it does
mechanism and evidence for each claimImproved collagen synthesis
Critical for healthy skin, joints, and connective tissue
Enhanced calcium absorption
Improves calcium uptake and bone health
Antiviral support
May help reduce frequency and severity of viral infections
Wound healing acceleration
Supports faster tissue repair and healing
Others take these for the same thing
Same goal, different mechanism — check any of them against this one
Probiotics for Autoimmune Disease Support
Gut health & immune modulation
10-100 billion CFU daily
B
60%
Vitamin D3
Bone health & immune support
1000-2000 IU
A
85%
Collagen Peptides
Skin health & joint support
5-15g
B
85%
Bone Broth Collagen
Gut healing & collagen support
20-40g powder
B
85%
Vitamin B7 (Biotin)
Hair, skin & nail health
300-5000 mcg
A
80%
Vitamin B3 (Niacinamide)
Energy & skin health (no flush)
100-1000 mg
A
88%
Every pair we checked
12 combinations scored by the engine
L-Lysine + Arginine AKG
Lysine and arginine compete for absorption and cellular uptake
Needs attention
22
L-Lysine + Caffeine
No documented interaction either way
No known interaction
70
L-Lysine + Creatine Monohydrate
No documented interaction either way
No known interaction
70
L-Lysine + Whey Protein
No documented interaction either way
No known interaction
70
L-Lysine + Lactase
No documented interaction either way
No known interaction
70
L-Lysine + Bovine Collagen
No documented interaction either way
No known interaction
70
L-Lysine + DHA
No documented interaction either way
No known interaction
70
L-Lysine + Turmeric
No documented interaction either way
No known interaction
70
L-Lysine + Fish Oil (EPA/DHA)
No documented interaction either way
No known interaction
70
L-Lysine + Calcium Carbonate
Lysine enhances calcium absorption
Works better together
78
L-Lysine + Zinc Gluconate
Both support immune function and wound healing
Works better together
78
L-Lysine + Vitamin D3
Both essential for collagen synthesis
Works better together
82
Dosage
Daily1-3g
Maintenance500-1500mg daily
Immune support1-3g daily
Antiviral therapy1-3g daily (up to 6g during outbreaks)
Collagen support1-2g daily
Before you take it
VeganYes
When to expect it
First Effects1-2 weeks for immune and antiviral benefits
Peak Benefits6-12 weeks for collagen and bone health benefits
Deficiency DevelopmentWeeks to months with inadequate protein intake
Toxicity OnsetRare, weeks to months with very high doses
How to measure it
MarkerPlasma lysine levels
Optimal150-300 μmol/L
Deficient below<100 μmol/L
FrequencyOnly if monitoring protein status or immune function
What people actually reported to the FDA
CAERS, 88 reports naming it as the suspectMost reported effects
Excluded from the list above: choking (36), dysphagia (14), foreign body (12). Those are people struggling with the tablet itself, not with the compound.
Named as the suspect
88 reports
of 125 that mention it at all
Serious outcome
85%
hospitalisation, emergency room or worse
Other Serious or Important Medical Event62
Life Threatening24
Visited a Health Care Provider13
Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →
What actually reaches you
The label counts the carrier, your body does not
Absorption
Very high 90 of 100 · best absorbed form of this compound
Delivered daily
1800 mg
Cost per 100 mg delivered
$0.03 comparative — uses the absorption score, not a measured percentage
Works better with
+
Vitamin C
Both essential for collagen synthesis
Complementary roles in collagen formation and immune function · level A
+
Calcium
Lysine enhances calcium absorption
Improves calcium transport and bone mineralization · level B
+
Zinc
Both support immune function and wound healing
Complementary roles in immune and tissue repair · level BWhat not to take with L-Lysine
!
Arginine
Lysine and arginine compete for absorption and cellular uptake
Competition for transporters and metabolic pathways · major significance
!
High Protein Meals
Large protein meals may reduce lysine absorption
Competition with other amino acids · moderate significanceMedication interactions
Discuss these with a pharmacist before combiningLysine may increase antibiotic nephrotoxicity
What to do: Use caution and monitor kidney function
Lysine enhances calcium absorption
What to do: May improve calcium effectiveness
Available forms
L-Lysine (Free Form): Well-absorbed, Immune support, Antiviral properties, Affordable
Food sources
Meat and poultry
1.5-2.5g per 100g · 90
Fish and seafood
1.8-2.3g per 100g · 90
Dairy products
0.8-2.0g per 100g · 85
Legumes (limited)
0.6-1.2g per 100g · 75
Too little
- Frequent infections and poor immune function
- Slow wound healing and tissue repair
- Poor growth and development in children
- Fatigue and weakness
- Hair loss and brittle nails
- Anemia and reduced protein synthesis
- Calcium absorption problems
Too much
- Rare with oral supplementation:
- Gastrointestinal upset and diarrhea
- Kidney discomfort (very high doses)
- Gallstone formation (theoretical)
- Generally excellent safety profile
Who benefits most
immune-support
Essential for optimal immune system function
1-3g daily
antiviral-herpes-support
May help reduce viral outbreak frequency and severity
1-3g daily (higher during outbreaks)
collagen-skin-health
Critical for collagen synthesis and skin health
1-3g daily
bone-health-calcium
Enhances calcium absorption and bone mineralization
1-2g daily
vegetarian-vegan
Often deficient in plant-based diets
1-2g dailyWhere to buy it
Look for L-Lysine at 1-3g per serving. The form that matters here is L-Lysine (Free Form).
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What else affects it
Beyond other supplements
!
High protein meals
Large protein meals may reduce lysine absorption
Competition with other amino acidsHow it works
- Essential for antibody and immune protein synthesis
- Required for collagen and elastin cross-linking
- Facilitates calcium absorption and bone formation
- Interferes with viral replication mechanisms
- Essential for carnitine synthesis and fat metabolism
- Important for growth hormone and enzyme production
Key findings
what the evidence supports- Essential for immune function and antibody production
- Effective for reducing herpes simplex virus outbreaks
- Critical for collagen synthesis and wound healing
- Important for calcium absorption and bone health
Sources: NIH Examine.com · data reviewed 2026-08-02
Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →
Common questions
What are the benefits of L-Lysine?
Documented effects: Enhanced immune function; Improved collagen synthesis; Enhanced calcium absorption; Antiviral support. Supports immune system and antiviral activity
How much L-Lysine should you take per day?
The common daily range is 1-3g. By goal — maintenance: 500-1500mg daily; immune support: 1-3g daily; antiviral therapy: 1-3g daily (up to 6g during outbreaks); collagen support: 1-2g daily.
When is the best time to take L-Lysine?
Empty stomach. First effects are typically reported within 1-2 weeks for immune and antiviral benefits.
What are the side effects of L-Lysine?
At excessive doses: Rare with oral supplementation:, Gastrointestinal upset and diarrhea, Kidney discomfort (very high doses), Gallstone formation (theoretical), Generally excellent safety profile. Safety rating at normal doses is 8 out of 10.
What should you not take with L-Lysine?
Separate it from Arginine, High Protein Meals by two to four hours. Lysine and arginine compete for absorption and cellular uptake
Does L-Lysine interact with medications?
Documented interactions with aminoglycoside-antibiotics, calcium-supplements. Discuss these with a pharmacist before combining.
How do you know if you need L-Lysine?
The marker is Plasma lysine levels, optimal range 150-300 μmol/L. Common deficiency signs: Frequent infections and poor immune function, Slow wound healing and tissue repair, Poor growth and development in children, Fatigue and weakness.