Erythromycin ophthalmic ointment is a topical antibacterial ophthalmic ointment. Occasionally, allergic reactions such as eye pain, vision changes, persistent redness or irritation are seen, most of which are mild or transient, while the occurrence of systemic symptoms is rare, but it may still lead to serious adverse reactions such as herpetic epidermolysis bullosa rash, systemic drug rash, anaphylaxis, etc., which should attract the attention of clinical staff. Although erythromycin ophthalmic ointment is a topical drug, it does not have the common gastrointestinal reactions of oral and injectable preparations. However, long-term large-scale use can also cause adverse reactions of oral or injectable preparations, such as: nausea and vomiting and other gastrointestinal reactions, liver function damage, reversible neurological deafness, etc., because of the absorption of large amounts of erythromycin into the blood. Due to the abuse of antibacterial drugs, the resistance rate of erythromycin is particularly high, reaching 78.11% overall for Staphylococcus spp. and nearly 100% for Streptococcus pneumoniae. Therefore, it should not be used for a long time or frequently for skin and soft tissue infections, otherwise it will cause resistance to normal skin bacteria and lead to treatment failure.