Ornidazole is a 5-nitroimidazole derivative with actions similar to Metronidazole and Tinidazole and is used in the treatment of susceptible Protozoal Infections and also in Anaerobic Bacterial Infections. The antimicrobial activity of Ornidazole is due to the reduction of the nitro group to a more reactive amine that attacks microbial DNA, brings about loss of helical structure of DNA and subsequent DNA breakage thus inhibiting further synthesis and causing degradation of existing DNA.That is Ornidazole acts by inhibiting bacterial DNA synthesis and degrades existing DNA and causing degradation of existing DNA. That is Ornidazole acts by inhibiting bacterial DNA synthesis and degrades existing DNA.