“May all be happy, may all be healed, may all be at peace and may no one ever suffer."
The combination of Polymyxin B sulfate with Neomycin and Bacitracin zinc most nearly meets the criteria for an ideal topical antibacterial preparation. The spectrum of action encompasses virtually all pathogenic bacteria found topically and the three antibiotics are bactericidal. When used topically Polymyxin B sulphate with Neomycin and Bacitracin zinc are rarely irritating, and absorption from the skin or mucous membrane is insignificant. Polymyxin B sulphate attacks gram-negative bacilli including clinically isolated strains of Pseudomonas aeruginosa. This organism is conspicuously absent from the spectra of most other antibiotic agents, but it is highly susceptible to polymyxin B sulphate, which is acknowledged to be the most effective agent known for the treatment and prophylaxis of Pseudomonas infections. Neomycin provides bactericidal action against various gram-positive organisms and gram-negative organisms including many strains of Proteus. Neomycin is considered by various authorities to be the most effective antibiotic against Staphylococcus aureus which is among the more common aetiological organisms in topical bacterial infections. Bacitracin zinc is highly active against gram-positive bacilli and cocci and extends the spectrum to include haemolytic streptococci, thus completing the anti-bacterial range of this Ointment. There is overlapping of the bactericidal spectra of these three antibiotics, thereby providing increased activity through combined antibiotic action.