Metronidazole is a nitroimidazole compound that possesses antibacterial and antiprotozoal activities. It is effective against anaerobic protozoal parasites and against a broad range of anaerobic bacteria.
Metronidazole has a strong antibacterial activity against anaerobic cocci, anaerobic Gram-negative bacilli and anaerobic spore-forming Gram-positive bacilli.
Bactericidal actions of metronidazole against obligate anaerobes include its penetration into the bacterial cell, reductive activation and toxic effect of the reduced intermediate products. The intermediate product of metronidazole reduction causes cell death through its interaction with bacterial DNA.