The presence of brown sputum when the nasal cavity is sucked back requires consideration of an inflammatory reaction of the mucous membrane of the nasopharynx and throat, which commonly includes chronic rhinopharyngitis and sinusitis. The cause and condition can be clarified by examining routine blood tests, cranial CT, and if necessary, endoscopy of the nasopharynx. It is more common clinically to be infected with septic bacteria, such as Staphylococcus aureus and Pseudomonas aeruginosa. These suspected bacteria can cause damage to the mucosa of the nasal cavity, causing it to rupture and bleed, and the bleeding lesions have old blood clots, so there is a brown discharge mixed with sputum. Antibiotic treatment can be chosen, such as clindamycin and roxithromycin drugs.