My sister has just recently been prescribed seroquel - she's been taking it for about 3 weeks now. I know that its an antipsychotic and should help the hallucinations and her hearing things go away. except its not yet. they have even increased the dosage and prescribed another antipsychotic - risperdal. How long does it take? or will this be something that she will have to live with? is it that it will just decrease the hallucinations?