eye cream study (which outperformed both vitamin K and vitamin C in periorbital wrinkle reduction) round out the photo-aging evidence base 13 14
Recent clinical studies have shown that ipamorelin can significantly boost growth hormone levels without raising cortisol or prolactin, helping patients experience measurable improvements in strength, body composition, and well-being
Why they work together: Stimulates Type I, III, and IV collagen Enhances retinol's anti-aging effects Minimal irritation risk Supports skin barrier function Application strategy: Layer together in same routine (peptide first) OR separate AM/PM Signal peptides vs neurotransmitter peptides with retinol Signal peptides (like Matrixyl, Syn-Coll): Best compatibility with retinol Work synergistically Can apply together or separately Neurotransmitter peptides (like Argireline, Leuphasyl): Good compatibility but better separated Different pH requirements may interfere Apply separately (AM vs PM) for best results Peptides to avoid combining with retinol AHA/BHA peptide combinations: Products that combine peptides with acids (glycolic, salicylic) Adding retinol on top = potential over-exfoliation Use peptide+acid products separately from retinol nights High-dose vitamin C + peptides + retinol: All three together may be too much for sensitive skin Vitamin C (L-ascorbic acid) can destabilize retinol Better to separate: Vitamin C AM, Peptides + Retinol PM See our glow peptides guide for complete skincare peptide protocols
Despite the lack of official approval, both compounds have accumulated substantial preclinical evidence and extensive anecdotal reports from users worldwide
