Bacitracin zinc is the zinc complex of bacitracin, which consists of a mixture of antimicrobial polypeptides produced by certain strains of bacillus licheniformis and by bacillus subtilis var. tracy and which on hydrolysis yields the amind acids L-cysteine, D-glutamic acid, L-histidine, L-lsoleucine, L-leucine, L-lysine, D-ornithine, D-phenylalenine and DL-aspartic acid.

It is applied topically in the treatment of local infections, mainly infections of the skin, ear and eye. It is often formulated in combination with other active ingredients in topical creams, powders and solutions, topical and ophthalmic ointments, and otic solution.