There are many reasons that cause the lips to be dry all the time, as follows: 1, the lips have been very dry may be caused by allergic lipitis and chronic lipitis, mainly due to human contact with certain allergens, resulting in the formation of chronic allergic inflammatory reaction, if the inflammation repeatedly does not subside, it is easy to cause the human body to appear long-term dry lips, bleeding and other adverse symptoms. 2, the lips have been very dry may also be due to diabetes The body’s lips are always dry. 3, cause the human body’s lips have been very dry does not exclude the lack of water, liver fire and lack of vitamins, these people will show the symptoms of lips have been very dry.