Second-generation antipsychotics (SGAs) are the first choice for the pharmacological treatment of first episode psychosis (FEP). FEP has a good responsiveness to treatment, but patients can be highly susceptible to adverse effects. Therefore, SGAs should be started at a small dose and any adverse effects evaluated. The proper duration of antipsychotic treatment for FEP in patients with remission of positive symptoms has recently been examined in long-term studies. However, to determine antipsychotic treatment should be continued, it is necessary to have a meaningful discussion with the patient and their family, and careful follow-up observation is necessary even after discontinuation of treatment.
 There is no definitive conclusion with respect to the symptomatic relief of at-risk mental state (ARMS) and delaying the onset of psychosis using SGAs. In contrast, the rate of transition of ARMS to psychosis is reported to be approximately one-third. Therefore, the administration of SGAs results in side effects in more than a few false positive cases. According to overseas guidelines for ARMS, antipsychotic treatment should be avoided for the prevention of psychosis and it is considered desirable to proactively treat comorbid diseases. On the other hand, in order to perform psychological interventions, a small dose of SGAs may be considered for symptom reduction. No randomized controlled trials that have tested the effect of antidepressants on ARMS exist. With respect to the effects of long-chain omega-3 polyunsaturated fatty acids on ARMS, a report has shown a significant decrease in the psychotic transition rate and another study reported no difference in the transition rate compared with placebo when using high-quality psychosocial intervention. Therefore, it is necessary to conduct further studies on its effects in the future.
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