Nail biting
This is usually just a habit and can be successfully treated with hypnosis. The client must genuinely want the change and unless there is an unconscious reason to continue nail biting, the change is usually made. It is often just a childhood habit that never stopped and is usually unconscious, in that most people don’t even know they are doing it.
Sometimes, the nail biting can be more than a habit. The person may be using nail biting as a stress response, but this is often evident by the condition of the fingernails and cuticles; they would normally be badly bitten and chewed, bleeding and very sore.
If there is no response to the initial hypnosis session, and the nail biting etc continues, it is likely that there is a deeper reason for the nail biting. In this case I would use EFT to delve deeper into the emotions behind the symptom to relieve the unwanted response.
For 95% of people though, nail biting is merely a habit and therefore effectively treated using hypnosis.