<p>Metronidazole, a nitroimidazole, is active against various anerobic bacteria and protozoa. Nystatin is a polyene antibiotic with antifungal activity. Neomycin is an aminoglycoside. It is bactericidal and active against some gram-positive and gram-negative organisms. Polymyxin is active against gram-negative organisms including Pseudomonas aeruginosa.</p>