In most cases these actions are harmless, but some people do them often enough to cause injury. Lip-biting syndrome refers to chronic (long-term) oral habits that lead to injuries of the lips, including dryness, peeling and soreness. Besides biting and licking the lips, the syndrome also includes more severe behaviors such as picking at the lips with fingernails.

Many people with this problem can injure their lips without even realizing it — for example, when they are stressed or worried — and may not immediately connect their symptoms with the habit.

Inflammation, peeling and flaking of the lips, chronic ulcers, and white areas on the lips can be caused by overexposure to the sun. These sun-related lesions can lead to lip cancer. However, there is no evidence that lip biting increases the risk of lip cancer. If your dentist or doctor thinks you may have an underlying disease causing your symptoms, he or she will biopsy your lip by removing a very small piece of tissue for examination under a microscope. The results of the biopsy will show whether the lesions are cancerous, or are part of a larger medical problem.

If you do not have a medical problem that is causing problems with your lips, your dentist will diagnose lip-biting syndrome by asking questions about your medical history and oral habits.

Other people cannot stop as easily. They may not be able to control the habit, or may be doing it in their sleep. For these people, dentists can provide soft splints to place on the teeth at night, which will help prevent injury. Moisturizing creams placed on the lips also can help. In some cases, medication to address an underlying psychological condition is required.

If your lips are inflamed, your dentist or doctor may prescribe a topical steroid cream.