Erythromycin ointment is an antibiotic preparation that can be used to treat skin infections. If a patient presents with redness and swelling of the nail along with separation of the nail and flesh, this may be due to a bacterial infection such as bacterial onychomycosis and the doctor may advise the patient to apply erythromycin ointment appropriately and watch for adverse reactions.
However, for other causes of separation of nail and flesh, such as fungal infections, viral infections, trauma and medication, erythromycin ointment may be less effective. It is therefore recommended that the medication be used under the guidance of a doctor.