I haven't done extensive research on the matter, but I always read that pica is caused by the body craving some sort of vitamin or mineral that it is deficient in. Have you tried giving him daily multivitamins?
With that said, I have been a sufferer of pica during my last pregnancy. I craved sand sooooooo bad. I was actually considering going to my front yard and grabbing a handful to eat. I of course didn't want to eat and bacteria so I was catching myself googling how to sterilize it! Lol. It is horrible and while I had enough restraint to not actually go through with it, I can see how a child wouldn't understand the risks. I actually did eat sand as a child. Maybe my body has some sort of deficiency that I don't know of?!?
~ wife to Harlan
, Mommy to Avy
(2) & Riley
(July 31, 2012)