Ans. c. 2 years (Ref: Niraj Ahuja 7/e p67)Multiple randomized trials have found that maintenance of antipsychotic medication reduces the risk of relapse over a period of up to two years."A meta-analysis of 6493 patients with schizophrenia in 65 randomized trials of 7 to 12 months duration found that patients who continued on an antipsychotic experienced a lower relapse rate compared to patients withdrawn from an antipsychotic and receiving placebo (27 versus 64 percent; number needed to treat to benefit = 3, 95% Cl 2--3). Other studies of up to two years have found similar resultsAlthough the current consensus is that antipsychotic should be prescribed for 1-2 years after 1st episode of schizophrenia. Gitlan et al found that withdrawing the antipsychotic leads to relapse at rate of 80 % after one years of medication free and relapse at rate of 98% after 2 years of medication free. "-- Maudsley Prescribing Guidelines in Psychiatry 12/e p31Treatment Duration for Schizophrenia* 1st episode: 1-2 yearsQ* 2nd episode: 2-5 yearsQ* 3rd/Recurrent: LifetimeQ