Neomycin/Polymyxin B/Bacitracin Zinc

**Semantic type:** Amino Acid, Peptide, or Protein|Antibiotic|Pharmacologic Substance

**Definition:** A combination preparation containing the aminoglycoside antibiotic neomycin sulfate, the polypeptide antibiotic polymyxin B sulfate and bacitracin zinc, with topical antibacterial activity. Polymyxin B sulfate, a polypeptide produced by Bacillus polymyxa, binds to negatively charged phospholipids in the cell membrane, thereby altering the permeability of the bacterial cytoplasmic membrane. Neomycin sulfate, an aminoglycoside antibiotic, irreversibly binds to the bacterial 30S ribosomal subunit, thereby preventing mRNA from binding to the 30S subunit, causes misreading and inhibits protein synthesis.

**Synonyms:** - Neosporin Original