As an inveterate nail biter - lip chewer - fidgeter, I have long suspected that these undesirable behaviors may be manifestations of ADHD, with possibly some OCD generalized anxiety disorder thrown in for fun. As such, the most fruitful solutions may be pharmacological. Has anyone looked into this possibility?
As undesirable as these behaviors are, they may have fewer downsides than some of the more commonly recognized symptoms of ADHD. At the age of five, my younger brother was diagnosed with ADHD and started on Ritalin. He was literally bouncing off the walls, utterly incapable of functioning in a classroom (in the 1960s).
Meanwhile, I was gnawing my nails, cuticles and lips. But I stayed in my seat. My parents tried all the "remedies" mentioned in the article, with no success. Even when my parents explained to me why my brother was having problems, and I responded with "So what? I feel that way, too," it never occurred to anyone that I might share my brother's problem.
I once took Zoloft as part of treatment for depression. I believe my nail biting diminished somewhat, especially when I also took Ativan. When I switched to Bupropion, it returned with a vengance. I have never taken Ritalin, since I always did well in school and usually stayed in my seat (although my lips and fingertips bled all over my papers).
SF
P.S, I am not a doctor, but I play one in my mind.