Google BFRB support. You should find the BFRB support group website. Lots of great information there. BFRB is body focused repetitive behavior such as biting of toe nails, picking of skin, hair pulling, etc. Habit reversal training is known to help with BFRB's. You might want to consult a board certified behavior analyst with experience treating BFRBs.

My son will pick at his toenails (and fingernails) if they are not cut perfectly or if they get stubbed and their is a crack or other funny feeling...Likely my son prefers to have his feet in socks and often shoes, so he doesn't pick often, just in bath/after. maybe some lotioninn could help, gives a sensation and is physical....

My son hasn't done that but he used to hit himself quite a bit. It sounds like anxiety to me. Can you substitute the behavior with something less injurious? Maybe a fidget cube or spinner, tearing paper (my son does that when he's nervous), even a "clicky" pen? Good luck.

I would think its OCD related also. I knew an adult woman not on the spectrum that also did that. She wore toe socks to try and stop herself.

He doesn't see his ABA therapist until next week. I will ask her thanks. His Meds may need to be adjusted.