It is uncertain whether maintenance drug treatment is required for all people with schizophrenia as around 20 per cent of individuals will only experience a single episode. While a high proportion respond to initial treatment with antipsychotic medication, around 80 per cent will relapse within five years of a treated first episode, which can be partly explained by discontinuation of medication. 

Risk factors for relapse include the presence of persistent symptoms, poor adherence to treatment, lack of insight and substance misuse. 

Many guidelines recommend informing the service user that there is a high risk of relapse if they stop medication in the next one to two years. Abrupt withdrawal dramatically increases the risk of relapse in the short to medium term, so withdrawal should be gradual, with regular monitoring for signs and symptoms of relapse. After the antipsychotic is withdrawn, monitoring should continue for at least two years.