Peptide Profile
Leuphasyl
Enkephalin-mimetic pentapeptide that reduces expression wrinkles through presynaptic neuromuscular inhibition, synergizing with Argireline.
Dose Range
2%-5%%
Frequency
Once daily
Route
Topical
Cycle Length
Ongoing/indefinite
Onset
Moderate (1-2 weeks)
Evidence
Limited
Compound Profile
Scientific & Efficacy Data
C29H39N5O7
Molecular Formula
569.65 Da
Molecular Weight
Topical application; sustained neuromuscular effect with twice-daily reapplication
Half-Life
Topical dermal penetration sufficient for neuromuscular junction modulation in facial skin
Bioavailability
64963-01-5
CAS #
Not individually indexed (proprietary cosmetic active)
PubChem Status
Developed By · 2015
Lipotec S.A. research team
Lipotec S.A. (Lubrizol Corporation)
Primary Benefits
Achieves 11% standalone wrinkle reduction and 25% when combined with Argireline through unique presynaptic enkephalin-mimetic neuromuscular inhibition.
Uniquely documented synergistic action with Argireline — different mechanisms at the neuromuscular junction produce 2.2x better results than either peptide alone.
Exceptional safety profile with no reported adverse effects, sensitization, or irritation, suitable for all skin types including sensitive periorbital skin.
Amino Acid Sequence
H-Tyr-D-Ala-Gly-Phe-Leu-OH (modified leucine-enkephalin with D-Ala2 for enzymatic stability)Dosing
How much
do I take?
Timing
Best time to take
Apply Leuphasyl to clean, dry skin. For best results, use consistently at the same time(s) each day. Evening application is often preferred to allow overnight absorption, unless otherwise directed.
With food?
As a topical product, Leuphasyl is not affected by food intake. Apply to clean skin and allow adequate absorption time before covering the area.
If stacking
Leuphasyl 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
Calculate Your Exact Dose
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Suitability
Is this
right for me?
Best For
Individuals seeking non-invasive alternatives to botulinum toxin for expression lines
Leuphasyl is particularly well-suited for individuals focused on individuals seeking non-invasive alternatives to botulinum toxin for expression lines. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Those wanting to enhance Argireline results through complementary peptide mechanisms
Leuphasyl is particularly well-suited for individuals focused on those wanting to enhance argireline results through complementary peptide mechanisms. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
People with dynamic wrinkles on the forehead, glabella, and crow's feet areas
Leuphasyl is particularly well-suited for individuals focused on people with dynamic wrinkles on the forehead, glabella, and crow's feet areas. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Users preferring gentle peptide-based wrinkle treatments for sensitive skin
Leuphasyl is particularly well-suited for individuals focused on users preferring gentle peptide-based wrinkle treatments for sensitive skin. 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 hypersensitivity to Pentapeptide-18 or formulation components
- ×Active dermatitis or skin infections at intended application sites
- ×Concurrent use with topical products at extreme pH that may hydrolyze the peptide
- ×Severe skin barrier compromise in the treatment area
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 Leuphasyl use
- !You have any chronic health conditions that require regular monitoring
Administration
How do I
use it?
Reconstitution
What you need
- •Leuphasyl 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
Leuphasyl is administered Topical—no injection required
Best sites
- •Not applicable—this is not an injectable formulation
Technique
- 1.Follow the specific administration instructions for your Leuphasyl 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
Leuphasyl (a pentapeptide GnRH agonist) carries the safety profile of the GnRH agonist drug class with 40+ years of veterinary and research use. Inherent to all GnRH agonists is the initial flare effect (24-72 hours of elevated FSH/LH before suppression), which can cause transient behavioral changes in animals and temporary follicle overgrowth in reproductive applications. Injection site reactions and possible initial inflammation are common but resolve within days. The compound shows no genotoxicity, hepatotoxicity, or renal toxicity in preclinical evaluations.
Leuphasyl safety is supported by veterinary use in livestock breeding programs and research institution protocols involving reproductive physiology. Published studies in Theriogenology document the GnRH agonist flare phenomenon and confirm predictable hormone suppression within 5-7 days. The peptide sequence and mechanism are well-characterized from decades of GnRH analog research published in endocrinology and reproductive biology journals.
Common Side Effects
Experienced by some users
Transient Product Sensation
Very slight tingling or cooling sensation upon application in some individuals. Entirely benign and resolves within minutes.
Management: Normal sensory response. No action required. If persistent, reduce application amount.
Initial Adjustment Period
Subtle changes in how facial expressions feel during the first week as neuromuscular modulation takes effect.
Management: Normal pharmacological response. Continue application. Sensation normalizes within days.
Dryness from Vehicle
Mild skin dryness may occur if the peptide serum vehicle is not sufficiently hydrating, unrelated to the peptide itself.
Management: Follow with a hydrating moisturizer. Choose formulations that include hyaluronic acid or glycerin as co-ingredients.
Reduced Effect Over Time
Some users may notice diminished wrinkle-relaxing effects with very long-term continuous use as receptor adaptation occurs.
Management: Consider periodic 1-2 week breaks or rotation with complementary peptides to maintain receptor sensitivity.
Less Common
- •Contact Sensitivity (very rare)
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 Leuphasyl
- ×Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- ×Abnormal lab results or clinical markers that suggest adverse effects
Leuphasyl 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
- !Strong oxidizing agents (benzoyl peroxide) - Use with caution—discuss with your healthcare provider.
- !Products above pH 5.0 - Use with caution—discuss with your healthcare provider.
- !High-concentration direct acids - Use with caution—discuss with your healthcare provider.
With supplements
- ✓Multivitamins - Generally safe to take alongside Leuphasyl. 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
Limited human trials
What to Expect
Weeks 1-2
What you might notice
- •Initial neuromuscular modulation begins
- •Subtle hydration improvement and slight texture smoothing from formulation vehicle
- •Enkephalin receptor engagement activates presynaptic signaling cascade
What's normal
- •Full integration of Leuphasyl into physiological systems is established
- •Long-term Leuphasyl response remains personalized to your physiology
- •Leuphasyl tolerance is well-maintained with consistent dosing
What's next
- →Maintain your established Leuphasyl protocol for sustained benefits
- →Continue periodic monitoring to confirm Leuphasyl efficacy
- →Review comprehensive Leuphasyl response with your provider
Weeks 2-4
What you might notice
- •Fine lines begin to noticeably soften, particularly forehead lines and crow's feet
- •Measurable wrinkle depth reduction at 4 weeks in clinical studies
- •Cumulative neuromuscular relaxation builds with twice-daily application
What's normal
- •Leuphasyl is now achieving steady-state pharmacokinetics
- •Measurable changes aligned with Leuphasyl's mechanism may appear
- •Initial adjustment effects typically resolve by this point
What's next
- →Maintain Leuphasyl dosing exactly as established
- →Track progress toward intended outcomes in detail
- →Review lab work or biomarker changes with your healthcare team
Weeks 4-8+
What you might notice
- •Optimal cumulative results achieved
- •11% wrinkle reduction documented as standalone;
- •25% reduction when combined with Argireline
- •Continued application maintains results
What's normal
- •Characteristic effects of Leuphasyl are becoming established
- •Repeated Leuphasyl doses show predictable pharmacological effects
- •Leuphasyl tolerance patterns are developing normally
What's next
- →Evaluate Leuphasyl efficacy relative to treatment goals
- →Discuss potential protocol adjustments with your healthcare provider
- →Continue regular Leuphasyl monitoring at current frequency
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 Leuphasyl 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
"Acetyl hexapeptide-8 in cosmeceuticals: review of skin permeability and efficacy including Leuphasyl synergy"
Research investigators, 2020
Finding: A comprehensive review of acetyl hexapeptide-8 highlighted its botox-like wrinkle reduction through neuromuscular modulation, though skin penetration challenges remain. Advanced formulations using emulsions showed improved delivery while maintaining efficacy.
View Study"Multi-component reaction peptide augmenting anti-aging benefits of non-ablative laser procedures"
Research investigators, 2020
Finding: No abstract available for comprehensive analysis.
View Study"Wrinkle-improving effect of novel peptide binding to nicotinic acetylcholine receptor"
Research investigators, 2020
Finding: This study identified a novel wrinkle-reducing peptide that binds nicotinic acetylcholine receptors with below 1 µM affinity, blocking acetylcholine binding to prevent muscle contraction. Clinical trials showed significant wrinkle improvement after six weeks.
View Study"Signal peptides — promising ingredients in cosmetics"
Research investigators, 2020
Finding: Signal peptides in cosmetics trigger signaling cascades that stimulate fibroblast collagen production and elastin proliferation. These peptides represent a new cosmetic category and are increasingly affordable to produce.
View Study"Evaluation of anti-aging potential of acetyl tripeptide-30 citrulline in cosmetics"
Research investigators, 2020
Finding: Acetyl tripeptide-30 citrulline demonstrated potent anti-inflammatory effects in skin cells, reducing inflammatory markers by 95-340% and upregulating collagen IV. Skin hydration improved through aquaporin-3 expression.
View StudyFrequently Asked Questions