There are several main causes of swelling in the nostrils, one is nasal vestibulitis, the second is rhinitis, sinusitis, and the third is caused by nasal cysts. First, nasal vestibulitis. Mainly long-term repeated digging nostrils, resulting in the inflammatory reaction of the nasal vestibular mucosa erosion. When the redness and swelling mainly avoid digging the nostril again, the surface can be coated with Bactrim ointment. Secondly, if it is caused by rhinitis and sinusitis, you can consider spraying the nose with the drug Cochlearia or Rayocort as well as taking oral rhinitis drugs, Canglizi rhinitis drops or rhinitis capsules. If the effect is not good, endoscopic surgery can be considered. Third, nostril cysts. The swelling is mainly caused by infection and can only be considered for surgical treatment after the inflammation is well controlled.