Are you watching him take his medication? It could be possible that he thinks he is okay because he's not taking the pills.
Some ideas could be:
- speak with his doctor and see how he's reacted in the past with his medications. I'm not sure how long you have been with him, so you may not know how he reacts, but his doctor will have it on file.
- check out side effects for Zyprexa (OCD/aggravation could be a side effect)
I do know that my fiancee took almost a month to get settled into his medications (he took about a three year break from them thinking he was "okay").
Oh, and do you know why he went off of the medication in the first place? Finding a new one--and soon--would be a good idea. He may not be happy with the side effects, whatever they are, and is avoiding taking the medication because of that.