Sputum that is yellow in color is mainly common when there is a bacterial infection of the respiratory system, more commonly a purulent bacterial infection. Most obviously there is an exudation of inflammatory secretions from the airways with a large amount of purulent inflammatory secretions containing dead and live pathogens, as well as shed tissue fragments and produced inflammatory material, commonly bronchitis and pneumonia. Clinically, sensitive antibacterial drugs such as amoxicillin clavulanate potassium, cefuroxime sodium, cefoperazone sulbactam sodium, roxithromycin, azithromycin, clindamycin, and levofloxacin can be chosen. At the same time, some phlegm-clearing drugs, such as carboxymethystane oral solution, amiloride syrup and myrtle oil, can be given appropriately.