Just wanted to pass along some possible suggestions for on-going behavioral modification for this. Like many of you, I don't want to take medication for this--even though I have taken one that worked a miracle--because of hoping to have more children and their safety in utero.
While I am convinced that this disorder has to do with imbalances, hormones, or other problems in the brain, or pyschiatric disorders caused by environmental factors such as being abused as a child, and is aggravated by many of the things we eat and chemicals that they put in foods these days, I think there has to be some way to deal with those everyday compulsions/feelings. Unless somone out there can do some really SOLID research, we could bat around all the possibilities and reasons we do this all day long.
And, just sitting on your hands, or putting on special nails, etc., isn't going to address the underlying compulsions/feelings that are still going to be there, such that when you ultimately start picking, you will end up looking like ground beef instead of just having measles. So, I'm trying to find similar acitivities that most closely mimic what I'm feeling as I pick, and especially afterwards. Clearly, I don't want to completely mimic the pain and blood.
So far, the best idea I've found is puzzles. Yes, this probably sounds crazy, but it has a lot of similarities. The looking, searching involved, the frustrations (similar to not being able to get it all out), the "joy" from making a piece fit (similar to getting it all out), and especially the endless hours at a time that are spent at this activity, even though you are sick and tired of it, but just can't stop, to the point that you are exhausted and in a certain level of pain. In many ways, I hate doing puzzles, just like I hate the picking, but it can still be quite addictive.
The other idea combined with this is to alter the lights where you primarily pick. Don't go completely dark, but have light that won't reveal the detailed marks on your face. I have a closet off of my bathroom that works well. Of course, this requires you to actually remember to adjust the lights. And, both ideas require will power and determination.
Have I quit picking? No. I think this is an ongoing process. Long ago (32 years old and started picking when I became a teenager), I realized that there was never going to be a night and day, magical cure for this. Some days are just going to suck. But, we just have to get back on our feet and try, try again. I can lament about my past and even my present, and detail everything that's ever gone wrong, but that's not going to change the fact that today I am faced with this compulsion and tomorrow will be more of the same.