Tetrapeptide-30 Best Peptide Anti-Blemish Dark Spot Fading Soothing Tetrapeptide-30 at a glance Peptide composed of amino acids proline, glutamic acid, and lysine Helps interrupt pathways that lead to skin discolourations Has soothing properties Can revitalize a dull skin tone Tetrapeptide-30 description Tetrapeptide-30 is a synthetic peptide containing the amino acids proline, glutamic acid, and lysine. It acts on and within specific targets of skin to reduce factors and interrupt the pathways that lead to the appearance of discolourations and uneven skin tone. Tetrapeptide-30 also has skin-calming ability and can help revitalise a dull skin tone. It is supplied in a blend with glycerin and water, and the blend’s usage level for efficacy is between 0.5–5%.