Bacitracin Zinc

Bacitracin zinc is a complex of cyclic peptide antibiotics produced by the Tracy-I strain of Bacillus subtilis The commercial preparation is a mixture of at least nine bacitracins with bacitracin A as the major constituent. Today it is most often used topically to treat skin, ear and eye infections. ^{1, 4}

Bacitracin inhibits peptidoglycan synthesis in bacteria by blocking phosphorylase reactions, some of which occur during cell wall synthesis. Development of resistance to bacitracin is rare. ⁴

This antibiotic inhibits many organisms found on skin, such as hemolytic and nonhemolytic Streptococcus spp., coagulase-positive Staphylococcus spp., and is often combined with other antibiotics that have a gram negative spectrum of activity. Zinc increases the activity of bacitracin due to zinc's astringent properties which decrease inflammation. ⁴

In animals intended for food, such as chicken, turkey, and swine, bacitracin zinc is used for the prevention of necrotic enteritis caused by Clostridium perfringens susceptible to bacitracin zinc. ²

References:
REF FILE 324-DAC