A three-month-old baby with phlegm in the throat may have pharyngitis or respiratory infection problems, or it may be a backflow of nasal secretions or failure to swallow after eating milk. Therefore, parents are advised to first distinguish the cause of phlegm in the throat and choose the treatment according to the baby’s condition. Generally speaking, if there is only a simple phlegm in the throat, it can be treated by taking medicine or nebulization, which is more effective and does not cause serious harm to the baby’s body, and the recovery is faster and will not affect the baby’s health. But whether taking medicine or nebulization treatment, it should be done under the guidance of a doctor to avoid improper operation or improper medication, which will affect the child’s health. If the symptoms of phlegm in the baby’s throat are more serious and directly affect the child’s feeding or breathing difficulties, you should go to a regular hospital for examination to see if there is a possibility of upper respiratory tract infection, bronchitis or pneumonia, and also make sure to exclude laryngitis, which comes with a fierce condition, manifested as hoarseness, phlegm in the throat and difficulty in inhaling. Therefore, it is necessary to choose the treatment according to the doctor’s diagnosis and the baby’s physical state. If more phlegm does exist, the phlegm can be sucked out by professional medical means, together with the treatment of taking medication to help the baby solve the symptoms of phlegm in the throat. Parents are advised to pay attention to their baby’s physical condition in daily life, and to seek medical attention in time if there is phlegm in the throat or other uncomfortable reactions, so as not to miss the best time for treatment and avoid causing adverse effects on the baby’s body.