Cough with yellow sputum took antibiotics ineffective, there may be a number of reasons, common may be the medicine is not appropriate, or the medication course is insufficient, the drug is not sensitive to factors such as the cause. 1. The wrong medicine: not all coughs with yellow sputum are caused by bacterial infections, if other pathogens such as fungi, chlamydia, viruses and other infections caused by coughing, coughing yellow sputum, taking conventional antibiotics such as amoxicillin, cephalosporins are not any effect. 2. Insufficient medication course: antibiotics are usually used 72 hours after the lung infection to determine the efficacy, if the medication course is insufficient, the efficacy of the drugs can not be scientifically determined. 3. Drugs are not sensitive: antibiotics are more types of antibiotics, their antibacterial spectrum is also different, if the selected antibiotics are resistant to pathogens, the use of antibiotics will not be able to achieve the desired effect, the symptoms will not be able to improve. Cough yellow sputum may also be caused by inhalation of foreign bodies and other reasons, it is recommended to cough yellow sputum patients timely medical care, improve the relevant laboratory tests to clarify the cause of the disease, to give targeted treatment.