One-month-old babies with phlegm may be choking on milk, cold and flu, pediatric pneumonia, etc., can be treated through general, medication and other methods. 1. choking on milk: generally no special treatment, parents feed the baby appropriate water to dilute the milk in the throat, gently patting the back of a month-old baby after feeding, can effectively alleviate the symptoms of a month-old baby with phlegm. 2. Cold and flu: Parents should pay attention to the baby’s rest time, to ensure adequate sleep, reduce the outing. You can choose to use saline nebulizer inhalation to dilute phlegm under the guidance of a professional physician to promote its discharge, and if necessary, can follow the doctor’s instructions for the use of aminoglutethimide oral solution and other drugs for treatment. 3. Pediatric Pneumonia: Parents should avoid taking their babies to crowded environments and pay attention to their babies’ hygiene. For bacterial infections, you can choose to use cefixime granules, benzathine sodium capsules and other drugs; for adenovirus infections, you can use ribavirin and other drugs; for Mycoplasma pneumoniae infections, you can use azithromycin and other drugs for treatment. All of the above drugs should be used under the guidance of a doctor, avoid self-medication. There are other causes of phlegm in babies, and it is recommended to consult a specialist for evaluation and treatment.