Postnasal drip syndrome, that is, due to nasal and sinus diseases, causing nasal secretion backflow to the postnasal pharynx and other parts of the throat to cause coughing and other symptoms, other symptoms are: foreign body sensation in the throat, nasal congestion, runny nose, hoarseness, nausea and vomiting and so on. 1. Foreign body sensation in the throat: due to the nasal secretion stimulation of the throat will cause discomfort in the throat, there is a foreign body sensation, and some will also be manifested as a shrinking phlegm back to the symptoms. 2. Nasal congestion, runny nose: due to their own nasal diseases, so it will cause nasal congestion, runny nose, some may also cause nasal pain, itching, sneezing, tears, and decreased sense of smell and other symptoms. 3. Hoarseness: Due to localized drip fluid irritation, it may affect the vocal cords, thus causing hoarseness. 4. Nausea and vomiting: irritation of the pharynx by the drip may stimulate the vagus nerve, causing nausea and vomiting. Patients with postnasal drip syndrome need to go to the hospital for examination first to clarify the cause of the disease and follow the doctor’s instructions for treatment.