Erythromycin has no therapeutic effect on gray nails. Gray nails, or onychomycosis, is a disease caused by the infection of the nails with ringworm, and treatment requires oral antifungal medication, such as itraconazole, terbinafine, etc. The main ingredient is bitter ginseng, salicylic acid, benzoic acid, and a variety of other ingredients. The main ingredients are bitter ginseng, salicylic acid, benzoic acid, boric acid, etc. The drug has the effect of inhibiting the growth of skin fungus, and also has the effect of stopping itching and dissolving keratin, which can be used for the treatment of tinea pedis, tinea cruris, etc. In clinical practice, it can be used for the treatment of tinea pedis and tinea cruris. However, due to the limited penetration effect of the drug, it is generally not used in the treatment of tinea pedis. Erythromycin is a macrolide antibiotic, the drug is mainly used for the treatment of a variety of bacterial infectious diseases, for fungal infections caused by gray nails have no therapeutic effect. When the gray nail, must be in the doctor’s guidance to use antifungal drugs treatment, not to self-medication.