The two most common causes of swollen and painful edges of the nostrils are: first, considered to be caused by inflammation of the hair follicles, sebaceous glands or mucous membranes. Second, the most common is pain caused by fire, dryness, congestion and erosion of the skin and mucous membranes. Whichever it is, the treatment is very simple. You can use gentamycin eye ointment or tobramycin eye ointment to apply, generally 3-5 days, the pain can basically be relieved. If the pain is more intense and there is a clear bulge to touch with something growing out, it is often seen as a nasal boil, which is an inflammation of the hair follicles and sebaceous glands, and should never be squeezed because this location is called the danger triangle and squeezing can cause the inflammation to spread. If this happens, you can take oral antibiotics, most commonly cephalosporin, azithromycin, etc.