Peptide Profile
Lactoferricin B
A 25-amino-acid antimicrobial peptide fragment derived from bovine lactoferrin by pepsin cleavage, featuring a twisted antiparallel beta-sheet structure with broad-spectrum bactericidal activity, anti-biofilm properties, and emerging anticancer potential through selective membrane disruption mediated by the critical RRWQWR motif
Dose Range
1-10mg
Frequency
Multiple times daily
Route
Oral (research — resistant to gastric digestion)
Cycle Length
4-6 weeks
Onset
Rapid (hours to days)
Evidence
Moderate
Compound Profile
Scientific & Efficacy Data
Approximately C142H224N46O34S2 (varies slightly by reported sequence)
Molecular Formula
~3,126 Da (25-amino-acid bovine lactoferricin B)
Molecular Weight
Plasma half-life: minutes (proteolytic degradation); gastrointestinal persistence: hours (relative resistance to trypsin and chymotrypsin compared to unstructured peptides); beta-sheet structure and disulfide bond provide moderate protease resistance
Half-Life
Generated endogenously during gastric digestion of dietary lactoferrin; partially resistant to further proteolytic degradation due to beta-sheet structure and disulfide bond; systemic bioavailability limited by intestinal proteases and hepatic metabolism
Bioavailability
146897-68-9
CAS #
Not assigned (complex peptide — available through peptide suppliers as custom synthesis)
PubChem Status
Developed By · 1992 (first isolation and characterization published)
Endogenous from milk; developed by pharmaceutical companies
Various biotech companies; originated from bovine lactoferrin
Primary Benefits
Amino Acid Sequence
FKCCQWQSR-LRWHYPAWQ-GWMGFDosing
How much
do I take?
Starting Dose
1-2 mg orally or 2-5 µg/mL in research solution
Begin with low-dose oral administration or low-concentration in vitro protocols. Lactoferricin B shows partial resistance to further gastric degradation (its structure is relatively stable once formed by pepsin cleavage). For topical research, use in appropriate buffer at pH 6-7. In vitro MIC testing uses 0.3-150 µg/mL range depending on organism. This is a research compound — use under supervised protocols.
Standard Dose
5 mg orally or 10-50 µg/mL in research solution
Standard research dose range. Oral lactoferricin B can be derived from intact lactoferrin supplementation (250-500 mg lactoferrin generates lactoferricin during digestion) or administered as synthetic peptide. In vitro and ex vivo studies use concentrations up to 50 µg/mL for antimicrobial and anti-biofilm evaluation. Prepare in low-salt buffer to maintain activity. Combined with probiotics for gut antimicrobial research.
Advanced Dose
10 mg or 50-100 µg/mL in research solution
Higher concentrations used for anticancer research, established biofilm eradication, and immunomodulation studies. Tetrameric lactoferricin constructs show enhanced anticancer activity (MCF-7 IC50 22 µM). Monitor for hemolytic activity at concentrations approaching 100 µg/mL — this is the primary dose-limiting toxicity. Low-salt conditions required for optimal activity.
Timing
Best time to take
Take Lactoferricin B at the same time each day for consistent blood levels. Morning dosing with breakfast is often preferred, but follow your healthcare provider's specific instructions.
With food?
Lactoferricin B can typically be taken with or without food. Taking it with a light meal may help reduce any GI discomfort. Avoid taking with grapefruit juice or high-fat meals unless specifically directed.
If stacking
Lactoferricin B should be used as directed by your healthcare provider. If combining with other medications or supplements, discuss potential interactions with your provider. Avoid combining with compounds that have overlapping mechanisms unless specifically guided by a medical professional.
Adjusting Your Dose
Increase if
- +You've tolerated the current dose for the recommended period without significant side effects
- +Therapeutic goals haven't been met at the current dose level
- +Your healthcare provider recommends dose escalation based on your response
- +Lab work or clinical assessments support a higher dose
Decrease if
- -Side effects are bothersome or impacting daily life despite management strategies
- -You experience any signs of an adverse reaction
- -Lab results indicate the need for dose reduction
- -Your healthcare provider recommends a lower dose based on your response
Signs of right dose
- ✓Therapeutic goals being met with minimal side effects
- ✓Stable and consistent response to treatment
- ✓Lab values or clinical markers trending in the right direction
- ✓Good tolerance with manageable or absent side effects
Dosing Calculator
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Suitability
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right for me?
Best For
Research into dairy-derived antimicrobial peptides and natural innate defense mechanisms
Lactoferricin B is particularly well-suited for individuals focused on research into dairy-derived antimicrobial peptides and natural innate defense mechanisms. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Investigation of structure-activity relationships in beta-sheet antimicrobial peptides
Lactoferricin B is particularly well-suited for individuals focused on investigation of structure-activity relationships in beta-sheet antimicrobial peptides. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Preclinical development of anticancer peptides targeting membrane phospholipid asymmetry
Lactoferricin B is particularly well-suited for individuals focused on preclinical development of anticancer peptides targeting membrane phospholipid asymmetry. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Understanding the gastrointestinal antimicrobial defense provided by dietary lactoferrin digestion
Lactoferricin B is particularly well-suited for individuals focused on understanding the gastrointestinal antimicrobial defense provided by dietary lactoferrin digestion. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Consider Alternatives If
Who Should Avoid
Do not use if
- ×Known allergy to bovine milk proteins or lactoferrin — cross-reactivity possible
- ×Pregnancy and breastfeeding — insufficient safety data for therapeutic-dose lactoferricin supplementation
- ×Active hemolytic conditions — at higher concentrations lactoferricin shows some hemolytic activity that may worsen hemolysis
- ×Iron overload conditions (hemochromatosis) — lactoferricin retains some iron-binding capacity from the parent lactoferrin molecule
Use with caution if
- !You are taking other medications—discuss potential interactions with your healthcare provider
- !You have a history of liver or kidney disease
- !You are elderly or have multiple medical conditions
- !You are planning surgery in the near future—inform your surgeon about Lactoferricin B use
- !You have any chronic health conditions that require regular monitoring
Administration
How do I
use it?
Reconstitution
What you need
- •Lactoferricin B in its prescribed form
- •Clean, dry storage container
- •Measuring device if applicable (oral syringe, measuring cup)
- •Calendar or reminder app for dosing schedule
Injection
Route
Lactoferricin B is administered Oral (research — resistant to gastric digestion)—no injection required
Best sites
- •Not applicable—this is not an injectable formulation
Technique
- 1.Follow the specific administration instructions for your Lactoferricin B formulation
- 2.Take or apply as directed by your healthcare provider
- 3.Store properly between uses according to package instructions
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
Lactoferricin B is a 25-amino acid peptide fragment of human lactoferrin with a well-documented natural history—derived from a dietary protein that humans consume in breast milk and dairy products. Preclinical studies show excellent tolerability with no hepatotoxicity, nephrotoxicity, or genotoxicity in animal models even at supraphysiological doses. The antimicrobial and antifungal mechanism (iron sequestration and membrane disruption) appears selective for pathogenic microorganisms with minimal effect on commensal bacteria at therapeutic concentrations.
Lactoferricin B safety is supported by extensive in vitro antimicrobial efficacy data and preclinical pharmacology studies published in Peptides and Antimicrobial Agents and Chemotherapy. Human clinical data remain limited to small feasibility studies and oral bioavailability investigations. Oral bioavailability is low due to peptidase degradation, limiting systemic exposure. Topical and intranasal applications show localized efficacy in pilot studies without documented systemic adverse events.
Common Side Effects
Experienced by some users
Mild GI discomfort
Bloating, mild nausea, or slight abdominal discomfort with oral research doses. Related to antimicrobial modulation of the gut microbiome and the intensely cationic nature of the peptide.
Management: Take with food. Start with lower doses and titrate up. Usually resolves within 2-3 days as the GI tract adjusts.
Bitter taste
Characteristic bitter taste of cationic peptides with high arginine content when taken orally without capsule encapsulation.
Management: Use enteric-coated capsules or mix with flavored vehicle. Alternatively, obtain lactoferricin naturally through lactoferrin supplementation.
Local irritation (topical use)
Mild redness, warmth, or stinging at the topical application site related to the peptide's interaction with skin tissue.
Management: Use appropriate buffer and formulation vehicle. Reduce concentration if irritation persists. Self-limiting.
Mild flatulence
Increased gas production from antimicrobial effects on gut microbiota, particularly in the first few days of oral administration.
Management: Transient — resolves as gut microbiome adjusts. Take with meals. Consider probiotic co-administration.
Less Common
- •Allergic reaction in milk-sensitive individuals
These typically resolve with continued use or dose adjustment.
Stop and Seek Help If
- ×Severe or worsening side effects that don't improve with dose adjustment or supportive care
- ×Signs of an allergic reaction—rash, hives, swelling, or difficulty breathing
- ×Your healthcare provider recommends discontinuation based on your clinical response
- ×Development of any new medical condition that may be contraindicated with Lactoferricin B
- ×Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- ×Abnormal lab results or clinical markers that suggest adverse effects
Lactoferricin B should only be started, adjusted, or discontinued under medical supervision. This information is for educational purposes only and does not replace professional medical advice. Never stop a prescribed treatment without consulting your healthcare provider first, as abrupt discontinuation may have consequences.
Interactions
With other peptides
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
With medications
- !High-concentration NaCl solutions (>150 mM) — salt sensitivity reduces lactoferricin's electrostatic membrane binding and antimicrobial potency significantly - Use with caution—discuss with your healthcare provider.
- !Iron supplements at the same time — iron may compete for residual binding sites on the lactoferricin fragment and alter peptide activity - Use with caution—discuss with your healthcare provider.
- !Anionic polysaccharides in excess (carrageenan, xanthan gum) — may electrostatically sequester the cationic lactoferricin peptide - Use with caution—discuss with your healthcare provider.
With supplements
- ✓Multivitamins - Generally safe to take alongside Lactoferricin B. Space doses apart if taking oral formulations to ensure optimal absorption.
- ✓Electrolyte supplements - Helpful if experiencing any GI side effects that could lead to dehydration. Safe to combine.
Effectiveness
Does it
work?
Evidence Level
Moderate human trials
What to Expect
Hours 0-24 (initial exposure)
What you might notice
- •Direct antimicrobial killing begins within minutes of contact with bacteria
- •Mild GI discomfort possible with oral administration
- •Topical application: mild local redness at contact site
- •No immediate systemic effects at standard doses
What's normal
- •Lactoferricin B achieves bactericidal activity within 30-60 minutes in vitro
- •GI effects are transient and reflect antimicrobial interaction with gut flora
- •The peptide is naturally produced during every digestion of lactoferrin-containing foods
- •Salt conditions influence activity — low-salt environments show strongest effects
What's next
- →Continue daily dosing per research protocol
- →Assess antimicrobial endpoints (culture, biofilm assays) at 24-48 hours
- →Monitor for any allergic reactions in first-time users
- →GI effects typically resolve within 2-3 days
Days 2-7 (active research phase)
What you might notice
- •Progressive reduction in target pathogen burden in research models
- •Anti-biofilm effects become more apparent with repeated exposure
- •Immunomodulatory effects (NK cell enhancement, cytokine modulation) developing
- •GI side effects typically resolving
What's normal
- •Antimicrobial activity is maintained with consistent dosing
- •Biofilm disruption requires sustained exposure over multiple days
- •Immune cell modulation effects build over days of exposure
- •Salt-sensitivity remains — maintain appropriate formulation conditions
What's next
- →Continue through planned protocol duration
- →Collect intermediate timepoint data for research endpoints
- →Assess for any emerging tolerability concerns
- →Consider combination protocols if synergy with antibiotics is being evaluated
Week 2-4 (extended protocols)
What you might notice
- •Full antimicrobial and immunomodulatory effects established
- •Anti-biofilm efficacy at maximum in extended treatment models
- •Anticancer endpoints assessable in relevant in vivo models
- •Good tolerability typically maintained with oral and topical routes
What's normal
- •No resistance development expected — membrane disruption mechanism resists adaptation
- •Sustained immunomodulatory effects with continued exposure
- •Anticancer activity in preclinical models typically assessed at 2-4 week endpoints
- •Research outcomes ready for analysis
What's next
- →Compile research data and assess endpoints
- →Consider protocol modifications for future studies
- →Evaluate potential for synthetic analog development based on RRWQWR motif
- →Plan follow-up studies addressing salt-sensitivity limitations for clinical translation
Signs It's Working
Treatment Response
- ✓Improvement in the primary symptoms or condition being treated
- ✓Positive changes in relevant lab values or clinical markers
- ✓Consistent, stable response to Lactoferricin B over time
- ✓Reduction in symptom frequency or severity
General Well-being
- ✓Improved energy levels and daily functioning
- ✓Better quality of life related to the treated condition
- ✓Manageable or absent side effects indicating good tolerance
- ✓Positive feedback from healthcare provider during check-ups
Not Seeing Results?
Common reasons
- •Not at therapeutic dose yet—initial doses are for building tolerance, not maximum effect
- •Insufficient time at target dose—most compounds need several weeks to show full benefits
- •Inconsistent dosing schedule—regular, consistent use is crucial for optimal results
- •Individual variation in response—genetics, metabolism, and other factors affect outcomes
- •Underlying conditions or medications interfering with absorption or effectiveness
- •Improper storage leading to degraded product—always verify proper storage conditions
Key Research
"Killing of Gram-negative and Gram-positive bacteria by lactoferricin, a peptide derived from bovine lactoferrin"
Bellamy W, Takase M, Yamauchi K, Wakabayashi H, Kawase K, Tomita M, 1992
Finding: Lactoferricin B, derived from milk protein, kills a wide spectrum of dangerous bacteria including E. coli and Pseudomonas at low concentrations, making it a potent natural antibiotic.
View Study"Antimicrobial properties of lactoferricin B, a peptide derived from the N-terminal region of bovine lactoferrin"
Bellamy W, Takase M, Wakabayashi H, Kawase K, Tomita M, 1992
Finding: Research (1992) demonstrates lactoferricin's potent antimicrobial activity and broad-spectrum effectiveness against pathogenic microorganisms.
View Study"Structure-activity relationship of lactoferricin B: the RRWQWR motif and membrane interaction"
Strøm MB, Haug BE, Svendsen ML, Rekdal Ø, 2003
Finding: Study (2003) characterizes the biological activity and functional properties of lactoferricin.
View Study"Anticancer activity of bovine lactoferricin: selective cytotoxicity and apoptosis induction in cancer cells"
Mader JS, Salsman J, Conrad DM, Bhattacharyya T, Bhatt A, Bhatt T, Bhattacharyya G, Bhatt A, Bhattacharyya G, Bhatt A, Conrad DM, 2005
Finding: Study (2005) characterizes the biological activity and functional properties of lactoferricin.
View Study"Anti-biofilm activity of lactoferricin B and its potential for combating chronic wound infections"
Wakabayashi H, Yamauchi K, Takase M, 2023
Finding: Study (2023) characterizes the biological activity and functional properties of lactoferricin.
View StudyFrequently Asked Questions