Self-Injury and Hair Pulling

Four-year-old girl with CdLS has been doing very well. Her play skills have been improving over the years. She can match objects, do a simple single puzzle piece, and play with a doll. She now understands the phrases, "come here," "we are going in the car," "we are going to school," "would you like a drink/food?" She knows and reacts to "No." She loves praise and all forms of support and fun. She always wants attention. Suddenly, she has started to pull her hair out. Within one hour, she had pulled half of her head full of long hair out. She was due two days later to have two teeth out and a biopsy on her esophagus. We had one tooth pulled out a day earlier, followed by pain management, Paracetamal and Dihydro codeine in large doses. This seemed to have no effect on the pain, but did send her "loopy" and very strange in her behavior. She has been tugging and pulling her hair out since, even with vigorous distraction, hats, and her hair "oiled" up. Last week I decided to cut the rest of her hair off. Since then, she has started to cut at herself with her nails, which I have cut down as low as possible. She attacks her arms, legs, face, neck, and tummy. I have put socks on her hands to stop her but she does pinch through this. Her body is now full of many little cuts and is a bleeding mass. How can I break this cycle of self-destruction?