Nasal passages on the lower side are often more obstructed when lying on the side. After turning to the other side, nasal passages that were not blocked or were less blocked on the upper side became blocked or more blocked on the lower side. On the other hand, the nasal cavity on the lower side is less obstructed. In addition, the sense of smell may be reduced to different degrees, and the speech is occluded nasal sound. Due to the long-term flow of nasal mucus through the nasal vestibule and upper lip, it can cause dermatitis or eczema, which is mostly seen in children. The nasal mucus can flow backward into the pharyngeal cavity, and symptoms such as cough and phlegm are present. This is one of the clinical symptoms in patients with chronic simple rhinitis. Differential diagnosis of nasal congestion located in the lower nasal cavity when lying on the side: 1. Cyclic nasal congestion and epistaxis in women Some women, when menstruation is about to come, nasal congestion like a cold will occur. Yet there are no other symptoms of a cold. After the menstrual period clears, the nasal passages are ventilated. This happens so often that these women have learned that once they have a stuffy nose for no reason, have not been exposed to cold, and do not feel like they have a cold, they know that their menstrual period is coming soon. There is also the case of bleeding from the nose at the onset of menstruation, and this epistaxis is what is known as inverted menstruation. This kind of epistaxis is what the people call epistaxis. When epistaxis occurs, the amount of menstruation can be reduced. 2.Deep side nasal congestion The main symptoms of nasal foreign body disease are deep side nasal congestion and purulent nasal discharge. Nasal foreign bodies are substances that come from inside or outside the nasal cavity. Nasal foreign matter can be divided into the following three types: ① non-living things such as candy wrappers, plastic plastic toys, buttons, necklace beads, glass beads, stones, soil and so on. ② plants such as beans, peanuts, fruit kernels. ③ animal species such as insects, roundworms, maggots, leeches and so on.