The present invention provides peptide-based peroxidase inhibitors having the formula AA1-AA2-AA3, wherein AA1 is a positively charged, negatively charged or neutral amino acid, AA2 is a redox active amino acid, and AA3 is an amino acid possessing a reducing potential such that AA3 is capable of undergoing a redox reaction with a radical of amino acid AA2 or a retro or retro-inverso analog thereof. The result of such a combination is a highly effective inhibitor of peroxidase activity that has potent antiinflammatory properties in widely diverse models of vascular disease and injury. Exemplary tripeptides effectively inhibit peroxidase mediated LDL oxidation, increase vasodilation in SCD mice, inhibit eosinophil infiltration and collagen deposition in asthma mice, inhibit acute lung injury, and decrease ischemic injury of the heart.