Nonapeptide-1

Nonapeptide-1 is a synthetic peptide used primarily as a skin-brightening agent at concentrations typically between 0.005-0.01%. Clinical studies and patch testing data demonstrate excellent tolerance with minimal irritation potential, as peptides of this size generally have low dermal reactivity and do not penetrate deeply enough to trigger significant inflammatory responses. While extremely rare sensitivities can occur with any peptide sequence, the molecular structure and typical formulation concentrations make this suitable for daily use in sensitive skin populations. Safety Notes: In commercial leave-on brightening/spot-correcting serums and creams, Nonapeptide-1 is commonly dosed at very low levels (often ~0.0005–0.005%) due to potency and typical supplier recommended use rates; the lowest observed levels in complex multi-peptide blends and mass-market brightening products can be around ~0.0001%. High-strength consumer-available targeted dark-spot serums and “peptide concentrate” products occasionally reach ~0.01% when used as a primary active, while rinse-off formats rarely use it or keep it at the very low end because of contact-time limitations and cost.