Leuphasyl
Also known as: Pentapeptide-18
Leuphasyl is a neurotransmitter-inhibiting peptide that reduces muscle contraction by mimicking enkephalins. It decreases acetylcholine secretion and is synergistic with Argireline for anti-wrinkle effects.
Research Status
Cosmetic ingredient with safety testing
For research purposes only. Not approved for human use. Not medical advice.
Research Areas
Side Effects
May occur in individuals with sensitive skin or those new to peptide-based cosmetics. Typically resolves within 24–48 hours. Discontinue use if irritation persists and perform a patch test before resuming.
Reported in isolated cases; likely due to localized neurotransmitter effects. Self-resolving and does not require intervention. Reduce application frequency if bothersome.
Possible in individuals with peptide sensitivities or allergies to other formulation ingredients. Discontinue immediately and consult a dermatologist if a rash, swelling, or severe itching develops.
May occur if the product is used without adequate moisturization. Ensure proper hydration with a compatible moisturizer, especially during initial use.
Dosing Reference
| Parameter | Value |
|---|---|
| Dose range | 2-5% |
| Frequency | Daily topical |
| Timing | Morning and evening |
| Route | Topical |
Apply to clean skin. Often combined with other peptides in formulations.
Research disclaimer
Figures drawn from published research literature and community logs. Not clinical recommendations. Consult a qualified professional. Research use only.
Reconstitution Guide
Do not use saline or bacteriostatic saline — use only bacteriostatic water for reconstitution
Do not shake the vial vigorously; gentle swirling prevents peptide degradation
Discard immediately if the solution appears cloudy, discolored, or contains visible particles
Use within 30 days of reconstitution when stored at 2–8°C
Do not freeze the reconstituted solution; freezing may denature the peptide
Use the PeptideVolt reconstitution calculator for your exact concentration
Molecular and Pharmacological Data
Leuphasyl is a synthetic peptide that mimics the structure and function of enkephalins, endogenous opioid neuropeptides. It inhibits acetylcholine release at the neuromuscular junction, reducing muscle contraction and facial expression lines. When applied topically, it works synergistically with other peptides like Argireline to diminish the appearance of wrinkles, particularly dynamic wrinkles caused by repeated muscle contractions.
Acetylcholine Inhibition
Leuphasyl reduces acetylcholine secretion from motor neurons, decreasing the strength and frequency of muscle contractions. This mechanism is similar to botulinum toxin but achieved through peptide-mediated neurotransmitter suppression rather than SNARE protein cleavage.
Enkephalin Mimicry
By mimicking endogenous enkephalins, Leuphasyl activates opioid receptors on presynaptic nerve terminals, which suppresses acetylcholine release through negative feedback mechanisms.
Anti-Wrinkle Synergy
Leuphasyl enhances the efficacy of Argireline and other anti-wrinkle peptides when combined in cosmetic formulations, producing additive or synergistic reductions in dynamic facial wrinkles.
- Leuphasyl functions as a neurotransmitter inhibitor, reducing acetylcholine-mediated muscle contraction in facial muscles
- It is structurally designed to mimic enkephalins, leveraging natural opioid signaling pathways for wrinkle reduction
- Topical application allows localized effects on facial muscles without systemic absorption or systemic side effects
- Clinical efficacy is enhanced when combined with complementary peptides such as Argireline in multi-peptide formulations
Track your Leuphasyl research
Free account. No credit card required.
Browse the Research Library
40+ peptide profiles with mechanism summaries, dosing data, and reconstitution guides.
View all peptidesResearch Use Only. All content on this page is provided for informational and educational purposes related to scientific research. Leuphasyl is not approved for human use by the FDA or any equivalent regulatory body. This is not medical advice. Do not use any substance discussed here for therapeutic, diagnostic, or preventative purposes. Consult a qualified healthcare professional before making any health-related decisions. The Peptide Volt does not endorse the use of any research chemicals. 18+ only.