There are several possible causes of itchy lips: 1. Swelling and itching within a short period of time, mostly caused by allergies, when the lips come into contact with food, drugs or lipstick or lipstick cosmetics that are suspected of causing allergies, causing angioneurotic edema, which can lead to instantaneous swelling of the lips within a short period of time and accompanied by itching. 2. Chronic lip infection, chronic lip infection is mostly caused by a lack of B vitamins in the body. 3, if the external environment is dry, windy, ultraviolet light is particularly strong can also induce lip inflammation, chronic lip inflammation patients will lead to dry lips, chapped, flaky, and also itchy symptoms, the symptoms of serious will also appear lip bleeding and erosion.