As the first choice drug for anti-anaerobic bacteria, metronidazole can effectively inhibit and kill periodontal pathogenic anaerobic bacteria such as melanin, gingival bacillus and intermediate bacilli. Its main therapeutic mechanism is the reduction of anaerobic bacteria after nitration, the production of cytotoxic substances, the inhibition of DNA synthesis of sensitive bacteria, and ultimately the death of bacteria.

Artificial bezoar metronidazole oral patch can solve the problem of large dosage of raw materials for oral administration of capsules, which is easy to cause severe liver first-pass effect, and metronidazole stimulates gastric mucosa and causes stomach pain and other side effects, and slow onset. . A sustained-release double-layer or single-layer oral patch made of the main drug metronidazole and artificial bezoar, and hydroxypropyl-beta-cyclodextrin plays an indispensable role as a binder.