Bronchitis in infants can develop into pneumonia if the treatment is not timely and thorough, because bronchitis is mainly a respiratory infectious disease caused by pathogens or chemical and physical factors that irritate the mucosa of the airways and the surrounding tissues, and does not involve the alveoli or interstitium of the lungs. Pneumonia is mainly an infectious disease of the lower respiratory tract. If bronchiolitis is not treated thoroughly, the pathogen can spread to the lower respiratory tract, thus causing pneumonia. Therefore, bronchitis in infants should also be actively treated, because infants are relatively small after all, it is recommended to choose anti-infective drugs under the guidance of specialists, the full amount of treatment, the full course of treatment, after adequate treatment to allow the doctor to assess whether to stop the drug, to prevent the complication of lung infections or lead to the recurrence of bronchitis.