• Non-adherence;
  • psychosis;
  • schizophrenia;
  • risk factors;
  • assessment;
  • interventions

Although non-adherence is common across all branches of medicine, psychotic disorders pose additional challenges that increase its risk. Despite the importance of non-adherence, clinicians generally spend too little time on assessing and addressing adherence attitudes and behaviors. Importantly, how adherence is measured significantly impacts the findings, and the most frequently employed methods of asking patients or judging adherence indirectly based on efficacy or tolerability information have poor validity. Novel technologies are being developed that directly assess adherence and that can also be used to both provide real-time feedback to clinicians and serve as an intervention with patients. Several treatments are available that can positively impact adherence. Among psychosocial interventions, those combining multiple approaches and involving multiple domains seem to be most effective. Although long-acting injectable antipsychotics are theoretically a very powerful tool to assure adherence and signal non-adherence, recent results from randomized controlled trials failed to show superiority compared to oral antipsychotics. These data are in contrast to nationwide cohort studies and mirror-image studies, which arguably include more representative patients receiving long-acting antipsychotics in clinical practice. This disconnect suggests that traditional randomized controlled trials are not necessarily the best way to study interventions that are thought to work via reducing non-adherence. Clearly, non-adherence is likely to remain a major public health problem despite treatment advances. However, increasing knowledge about factors affecting adherence and leveraging novel technologies can enhance its early assessment and adequate management, particularly in patients with psychotic disorders.