Antimicrobial and/or anti-inflammatory peptide compositions and therapeutic uses thereof are provided. The peptides and analogs or derivatives thereof may be used as an antimicrobial agent and/or as an anti-inflammatory agent. In certain embodiments, the peptides are cationic peptides. The peptides are useful for the treatment of inflammatory diseases, such as microorganism-caused infections, acne, and psoriasis. The peptides and peptide formulations may be used topically or parenterally.