The main function of metronidazole is anti-anaerobic bacteria, anti-trichomonas, mainly for the treatment of intestinal and extra-intestinal amoebiasis, vaginal trichomoniasis, pouch worm disease and cutaneous leishmaniasis, guinea worm infections and other diseases, and is now also widely used in the treatment of anaerobic bacterial infections. Metronidazole is a nitroimidazole derivative, which can achieve antibacterial efficacy by inhibiting the redox reaction of amoeba protozoa, causing the breakage of protozoa nitrogen chain; it can also inhibit the synthesis of bacterial deoxyribonucleic acid, interfering with bacterial growth and reproduction, and leading to bacterial death. Common adverse reactions to metronidazole include gastrointestinal reactions, such as nausea, vomiting, decreased appetite, abdominal pain, etc.; neurologic symptoms, such as headache, dizziness, sensory abnormalities, numbness of the limbs, ataxia, etc.; convulsions can be caused by high doses of the drug. A few patients may experience urticaria, flushing, itching, cystitis, dysuria, metallic taste in the mouth, leukopenia and other symptoms. In addition, it is contraindicated in patients with hypersensitivity to metronidazole or other nitroimidazole derivatives, in patients with active central nervous system disorders and blood disorders, and in pregnant women, lactating women, children, and patients with alcoholism. If you need to use metronidazole, it is recommended that you consult a professional doctor and follow the doctor’s instructions for standardized treatment, not blindly use the drug on your own.