Erythromycin is an antimicrobial agent of the macrolide class, which is commonly referred to as an anti-inflammatory drug. Erythromycin is more sensitive to Gram-positive bacteria, Mycoplasma pneumoniae, and Chlamydia. It is generally used in patients with penicillin allergy and can be used to treat tonsillitis, rhinitis, pharyngitis, otitis media and other otolaryngological diseases caused by Streptococcus pyogenes and Streptococcus haemolyticus. It can also be used for pneumonia, pneumonia caused by mycoplasma and chlamydia and urinary tract infections caused by some sensitive bacteria, and also for skin soft tissue infections. Erythromycin ointment, on the other hand, can be used for some infections of mucous membranes, such as ulcers and erosions of mucous membranes.