Leuphasyl

Leuphasyl is a synthetic pentapeptide (Tyr-D-Ala-Gly-Phe-Leu) developed by Lipotec as a cosmeceutical anti-wrinkle active. Classified under the INCI name Pentapeptide-18, it is an enkephalin analog that modulates calcium channel activity in nerve terminals. It is widely used in prestige anti-aging serums and eye creams, frequently combined with Argireline (Acetyl Hexapeptide-3) for synergistic wrinkle-relaxing effects without injection.

Leuphasyl mimics endogenous enkephalins by binding to opioid receptors on the presynaptic membrane of neuromuscular junctions. Receptor binding triggers a conformational change that initiates an intracellular cascade reducing nerve cell excitability. This dampens the calcium-dependent vesicular release of acetylcholine at the neuromuscular junction, attenuating the intensity of facial muscle contractions that produce expression lines. Unlike botulinum toxin, Leuphasyl acts upstream at the receptor level rather than by cleaving SNARE proteins, preserving partial muscle motility and avoiding the frozen appearance associated with injections. When formulated alongside Argireline, which operates via a distinct SNARE-complex interference pathway, the two peptides produce additive wrinkle reduction exceeding either ingredient alone.

In vitro studies published in Cosmetics (MDPI, 2014) confirm receptor-mediated modulation of Ca2+ channels consistent with enkephalin activity. Clinical split-face studies supplied by the manufacturer demonstrate statistically significant reductions in crow's-foot wrinkle depth after 28 days of twice-daily topical application versus vehicle control. The MDPI study concluded Leuphasyl is safe with no adverse effects and preserves facial expressivity unlike botulinum toxin. No independent peer-reviewed clinical trials exist as of 2026; evidence base is primarily manufacturer-sponsored.

Peptides commonly paired with Leuphasyl for synergistic effects.