It is normal to feel no sputum because sputum is caused by the backflow of nasal secretions into the nasopharynx, or increased secretion of glands in the pharynx and larynx due to inflammation in the pharynx, or increased secretion of airways due to inflammation in the lungs, all caused by inflammation in the nasal cavity or nasopharynx and lungs. If the inflammation is relieved the feeling of having phlegm is gone, so it is normal to have no phlegm. But once the symptoms of phlegm appear, also depends on the color of the phlegm, if it is yellow or green to consider the possibility of infection, need to use anti-inflammatory drugs, and also depends on the location of the phlegm, such as the nasal cavity or pharynx, lung inflammation caused by, and then give the appropriate treatment.