Metronidazole is an anti-anaerobic drug, in general, metronidazole is not harmful to the human body when put in shoes for a long time. Metronidazole belongs to the clinically used antibiotics, common dosage forms are tablets, capsules, lotions, gels, creams, etc., is a kind of anti-anaerobic drugs, anti-trichomonas drugs, can be used for intestinal and extra-intestinal amebiasis treatment, as well as vaginal trichomoniasis, pouch worm disease and cutaneous leishmaniasis, guinea worm infections and so on. Metronidazole has no role in treating foot odor or tinea pedis when put in shoes for long periods of time, and is generally not harmful to the human body. A few patients may experience nausea, vomiting, loss of appetite, abdominal cramps and other adverse reactions after taking metronidazole. It is recommended that patients strictly follow the doctor’s instructions to use the drug, do not change the dose of the drug or abuse the drug privately, the drug is prohibited for patients with active central nervous system diseases and blood diseases, for pregnant women, lactating women, children and alcoholics should be prohibited.