Coughs vary in length from cause to cause, but there is no generalization about how long it takes for a 6-month-old baby’s cough to clear up, and not all coughs can clear up on their own. Dietary causes, viral infections can be cured on their own, bacterial infections need medication to be cured, and allergies can only be cured by staying away from allergens. 1. Dietary reasons: 6-month-old babies are accidentally a small amount of milk into the trachea by mistake, the trachea is stimulated by a slight choking cough, this cough can be self-healing, a period of time can be relieved, do not have to a few days to be self-healing. 2. Virus-induced upper respiratory tract infections: common upper respiratory tract viral infections are self-limiting diseases, the cough will gradually heal itself, usually about 1 week of viral infections will be self-cured, the cough may last for about 3 weeks to heal itself. 3. Bacteria-induced bronchitis, pneumonia: If not treated in time, this type of disease will not necessarily be self-cured, with the progress of the disease will also aggravate the symptoms, the cough will also be prolonged. Under the guidance of a doctor, you need to find out the type of infectious bacteria and treat it with targeted medication. 4. Allergic asthma: cough will be repeated attacks, seasonal exchanges or allergic substances encountered more frequent coughing attacks, generally away from the allergens after the symptoms can be improved, can not be clear cough a few days to be able to self-cure. 6-month-old infants with frequent and prolonged coughing symptoms, it is recommended that timely medical treatment.