In some cases, erythromycin ointment is used to treat red buttocks in babies. At the same time, you need to pay attention to hygiene, wash the buttocks in time, keep them clean and hygienic, apply local emollient oil, prickly heat powder and other treatments, avoid the stimulation of urination and defecation, and stop using diapers for a while. It is best to let your baby’s buttocks dry in the air for a few more hours every day and let your baby’s buttocks sunbathe frequently to reduce the contact with urine. If it does not improve, you can refer it to the dermatology department of the hospital for treatment. Red buttocks, called diaper rash, is a common skin disease among infants, occurring in the baby diaper area refers to the limited patchy red spots or blisters that occur in the baby diaper bag area, and is an inflammatory skin lesion. There are many factors for the occurrence of diaper rash, the main one is that the skin of the buttocks is humid and stuffy for a long time, and the irritants in feces and urine can damage the skin and make the little buttocks red, and the secondary infection of bacteria, fungi and other microorganisms on the damaged skin will aggravate the degree of red buttocks. Erythromycin is a macrolide antibiotic that has antibacterial activity against most gram-positive bacteria, some gram-negative bacteria and some atypical pathogenic bacteria such as Chlamydia and Mycoplasma. Erythromycin ointment is used for purulent skin diseases such as impetigo, small burns, infections of ulcerated surfaces and common acne, and also for treating baby’s diaper rash with skin infections