This topic on our forum is on the same subject and includes some antinailbiting product links.
http://www.autism-pdd.net/forum/forum_posts.asp?TID=14789&am p;KW=nailbiting
My youngest son (social delays, no diagnosis yet) started to bite his fingernails in the spring -- he doesn't do it anymore. It might have been a stress reaction for him. Even though nothing major changed in his life, as our kids get older, they're faced with more expectations and demands that they maybe aren't ready for.
Anyhow, I don't have access to anti-nailbiting products here in Norway, so I just rubbed mint mouthwash on his fingers a few times. He doesn't like mint. After that, I only had to say "do I need to put some mint on your fingers?" and he'd quit. After awhile, the bad habit seemed to disappear completely, so I consider myself lucky.
Some people have been saying that zinc supplements reduce biting/chewing habits (like chewing on shirts), so that's one thing to consider, especially if your child is a picky eater and might have gaps in his diet.
You'll find information on oral sensory-seeking and products like chewelry if you browse around at this website:
http://www.sensory-processing-disorder.com/sensory-processin g-disorder-checklist.html
Good luck with everything.
Gum and chew tubes worked for Jayden. Heck im 25 and still bite my nails. Its just a bored/nervous habit I guess.
I remember starting a thread similar to this maybe 6 months ago or so ... not sure.
My kiddo was picking the skin off and it didn't seem to hurt him at all, even when it looked awful.
He did stop doing it eventually. Occasionally I will see him picking, but not as bad as before.
Try giving him something else to chew on? Gum works for my dd (also 4yo) but there have been other recent suggestions such as a chewy toy I can't remember the name of... My 4 yo ds is biting his finger tips. He is biting the skin at the tips and his nails are bitten down so low. He occasionally asks for a band aid if they start to bleed a little but no infections or major pain is apparent. He bites a lot when he is nervous, anxious or tired. He started this a couple of months ago, there were no changes at that time. Prior to this he was biting on his shirt for a few weeks and prior to that no biting or mouthing of at all. How can I help him reduce this behavior? I'm worried he'll get an infection in his fingers not to mention the germs this is introducing he gets sick so often this will make it worse!