You don't mention how long he's been doing this but have you considered anxiety? My son went through this. He's 5 now and it isn't so much a problem. However, I still catch him chewing on random things from time to time. He would chew his shirt so badly that it would be soaked and sometimes holes would appear. At the time, I couldn't figure it out. He had started school and we had a baby (should be so clear that this is what was causing his anxiety). However, it wasn't for me at the time. He seemed so excited about the new baby and loved her to pieces. Anyway, my son was in Occupational Therapy, for something unrelated, and I have learned some techniques. Gum is one. Whenever you catch him doing it, do not bring attention to the fact he is picking at his lip, it will only create more anxiety because he knows he's doing something he's not supposed to be doing. Instead, just offer him a piece of gum or really chewy candy (like a Now and Later). Chewing is very calming (think about it, adults often chew on pencils when they are stressed). Basically, you are giving him something more appropriate to do other than picking at his lip . It's a natural defense. If you find that it is happening more at certain times or certain places, have him drink yogurt or Jello through a straw (or a thick smoothie or shake). It's hard to suck out, and again, calming. Another technique is to trick him into taking deep breaths and distracting him. Ex: you catch him picking and you might start breathing in deeply and say, "Do you smell that?!!!" Get him to take deep breaths to try to smell. My son would always say, "NO! What do you smell? I don't smell anything." Unfortunately, I just lie. "....oh, I thought I smelled chocolate." :) Lastly, like others have posted, it can't hurt to buy a bunch of fun chapsticks. Keep them everywhere. In your purse, his pocket, the car, his nightstand, etc. He'll be less likely to pick if his lips are nice and moist. Plenty of fluids too, of course. However, even if he stops picking his lips, if it is anxiety related, he'll just start doing something else. Kids will suffer from anxiety from time to time and what we need to do is try and teach them ways to cope with it. All of these examples are a type of oral exercise but even regular exercise is calming. If you have an indoor trampoline, when you catch him, play a game. "how many jumps can you count up to on your trampoline." Or, any type of physical exercise. We will build obstacle courses indoors, wheel barrow races (with me holding his legs), have him push my heavy laundry basket into the laundry room, wear a heavy backpack, etc, jumping up and down on the floor 30 times. Get creative. The exercise can be something really simple. It is also very calming. I know how ridiculous this all sounds! That's exactly what I thought when my son started Occupational Therapy. However, it works. What you are doing is teach him problem calming skills to use later in life. When he feels stressed, here are easy ways to feel more in control and calm. When I'm stressed, I do some of the same. ...or have a big fat glass of wine. ha-ha. J/K. Good luck; he'll be okay.