I would be inclined to look into why he is excessively biting his nails, just due to the fact excessive nail biting is associated with stress/ nervousness /anxiety issues. I am a believer in finding a prevention rather than having to find a cure.
On a lighter note, I tell my children when they chew their nails ,, ‘ they are consuming more germs chewing their nails than you’d consume licking a toilet seat’ fingers retreat from mouths pretty rapidly!!
Good luck with your son!
Published 16th October 2019