Spitting up yellow sputum with a cold is usually due to a secondary bacterial infection on top of a viral infection, suggesting that the condition has worsened. Colds are usually caused by viral infections, and the main symptoms are nasal congestion, runny nose, cough, sputum, sore throat, etc. The runny nose and sputum caused by viruses are usually clear and watery, and the sputum is usually white. Virus-induced runny nose is usually clear water, cough sputum is usually white sputum. The presence of yellow sputum indicates secondary bacterial infection of the respiratory mucosa, causing respiratory mucosal congestion, edema, oozing yellow purulent secretions, which can lead to prolonged duration of the cold. If yellow sputum is present, antibiotics can be given to fight infection, and drugs such as cloxacillin, piperacillin and cefixime can be chosen for treatment. If the sputum is not easy to cough out, you can be given aminoglutethimide, bromhexine and so on to dissolve the sputum. Avoid alcohol and tobacco during the treatment period, and pay attention to keep warm. Yellow sputum can also be caused by other diseases, not necessarily related to colds. If the symptoms do not improve or worsen, it is recommended to go to the hospital for examination, to clarify the cause of the disease and treatment under the guidance of the doctor, do not delay, so as not to delay the disease.