Bacterial bronchitis can be treated with azithromycin, but clinical doctors prefer penicillin and cephalosporin antibiotics for bronchitis caused by bacterial infections. This is because these types of antibiotics kill bacteria by destroying the cell wall of the bacteria to achieve rapid bacterial killing. For the elimination of bacteria, azithromycin inhibits genetic material, so its anti-inflammatory strength is not as fast as penicillin and cephalosporins. However, azithromycin is an effective drug for treating atypical pathogenic bacteria, like mycoplasma, chlamydia, and legionella, and it is preferred for these types of infections. In addition, quinolones and aminoglycosides are prohibited for adolescents under 18 years of age, and if they are allergic to penicillin, cephalosporins also need to be used with caution, so the choice of antibiotics for this group of children is narrower, and only azithromycin can be chosen. Therefore, for children under 18 years old with penicillin allergy to bacterial bronchitis, azithromycin is the first choice.