I second or third the music suggestion. I always study with music.

There's a possibility you have comorbid ADHD. You at least have inattentional, and hypereactivity issues when your'e trying to concentrate, and ADHD medication might be helpful. I have a friend with schizoaffective who's hallucinations got worse, or weirder, I should say (lots of 10 foot tall bunnies), when she was put on adderall which is a stimulant, but a non stimulant ADHD med like Strattera, or possibly even Wellbutrin (although that's not helping my attention at all) could help your attention and ability to focus without worsening the hallucinations. Hallucinations often get worse on stimulants.