The invention encompasses hexapeptides consisting of alternating hydrophobic residues (B) at positions 2, 4, and 6, hydrophilic, charged residues (X) at positions 1 and 3, and a naphthylalanine (Nal), an aliphatic or aromatic residue (O) at position five, represented generally by the formula XBXBOB, which exhibit antimicrobial activity against infections caused by a variety of pathogens. These pathogens may include gram positive or negative bacteria, acid-fast bacteria such as mycobacteria, parasites, dermatophytes, or fungal pathogens. Typical fungal pathogens include Candida albicans and typical dermatophytes include Trichophyton rubrum and Trichophyton mentagrophytes. The hexapeptides of the present invention exhibit antifungal activity, antibacterial activity, desirable stability, and lack toxicity to the mammal receiving treatment.