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Leuphasyl (Pentapeptide-18)
Overview
Leuphasyl is a synthetic pentapeptide (Tyr-D-Ala-Gly-Phe-Leu) that mimics the N-terminal sequence of enkephalin and modulates acetylcholine receptor activity at the neuromuscular junction. It is proposed to stabilize the receptor in an inactive conformation, reducing the frequency of muscle fiber contraction without blocking neurotransmission.
Mechanism of Action
This mechanism is intended to yield a topical wrinkle-smoothing effect with cosmetic applications.
Research Summary & Key Findings
In vitro electrophysiology studies have shown that pentapeptide-18 reduces the amplitude of miniature endplate potentials in muscle preparations. Industry-supported trials have reported subjective improvements in periorbital and forehead lines after four weeks of topical use, though rigorous placebo-controlled designs and independent validation are limited. Clinical evidence in peer-reviewed dermatology literature remains sparse.
Clinical Status
Leuphasyl (Pentapeptide-18) is in the investigational stage. While preclinical and early-phase data exist, it has not received regulatory approval for clinical use in the United States.
Administration Routes
References
Primary literature
- PubMed: "Leuphasyl"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Leuphasyl"
Registered interventional and observational studies, including status and phase.
- PubChem: "Leuphasyl"
Chemical structure, molecular properties, and bioactivity data.
Study-level citations for this compound are being verified against the primary sources before publication. The database queries above return the current indexed literature in the meantime.
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View detailsNo lawful pathway today
Leuphasyl (Pentapeptide-18) is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so there is nothing for us to sell you here and no consultation to book. That can change: eight peptides moved back to a lawful pathway in February 2026.
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List Your PracticeDisclaimer: This information is provided for educational and research purposes only. It is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any peptide therapy. The Peptide Association does not endorse or recommend any specific treatment protocol. See our editorial policy for how this content is produced and reviewed.