Polymyxin Injection is a broad-spectrum antiviral drug commonly used in ophthalmology clinics. It is composed of multimolecular nucleotides and has good efficacy in a variety of viral infections, and can promote the formation of antibodies and stimulate the phagocytosis of macrophages. Currently, it is mainly used in the adjuvant treatment of viral keratitis, herpes simplex virus infection and chronic viral hepatitis. The method of use is intramuscular injection. If an allergic reaction or temperature increase occurs during use, the drug should be discontinued immediately. Viral keratitis also requires adjunctive other medications, such as antiviral eye drops.