Welcome at Healthcare Magic. I read your question and I understand your concern. Quitiapine does not cause hallucinations. It s most common side effects are dizziness, dry mouth, headache and excessive day time sleeping. Hallucinations like hearing voices or seeing things which are not present in real sense is commonly cause by Antidepressants like Escitalopram, anticholinergics and antihistamines. Quitiapine half life is 9-12 hours, 75 Percent excretes in urine. It would take atleast 12-24 hours to clear from the body. I would advise to take him to Psychitrist with full list of other medications that he has been prescribed. Hope it helps best. Don t forget to rate this answer. Take your best care and of your son. Regards Dr Ejaz