Dimer Tripeptide-43

Dimer Tripeptide-43 is a synthetic signal peptide typically used at very low concentrations (often ppm to <0.1%) to support barrier/repair signaling, and peptides in this use range are generally well-tolerated with low rates of irritant reactions in routine cosmetic patch testing. While true allergy is uncommon, any peptide can still trigger stinging or dermatitis in highly reactive or eczema-prone skin depending on the overall formula and penetration system, so it is best classified as very gentle rather than inert. Safety Notes: Dimer Tripeptide-43 is a specialty anti-aging peptide typically supplied as a dilute solution and is most commonly used in leave-on serums/eye creams at very low active levels; at the low end, it appears in multi-peptide blends where the individual peptide is around 0.0001–0.001%. The highest OTC consumer-available products that highlight this peptide (or use it as a key active rather than a trace component of a blend) generally top out around ~0.01% active due to cost, diminishing returns, and formulation/stability considerations typical for peptides; rinse-off use is uncommon and would usually be at the lower end.