Antipsychotics and dietary interventions: Pharmacodynamics, pharmacokinetics, and synergisms in therapy

Antipsychotic (AP) medications are the primary treatment for severe mental illnesses, including schizophrenia and severe mood disorders. APs are currently categorized into typical or first-generation APs and atypical or second-generation APs. Although both first-generation and second-generation APs are considered effective in treating psychotic symptoms in severe mental disorders, they differ in their mechanisms, treatment strategies, and side effect profiles. Because of their potential motor and metabolic side effects, which often compromise patient adherence and clinical outcomes, whether and how to use APs remains controversial. The use of dietary interventions in combination with APs is emerging as a viable strategy to reduce AP adverse effects while maintaining their efficacy and enhance patient adherence to treatment. In contrast to drugs that possess a well defined molecular mechanism of action, dietary interventions act in pleiotropic ways by nature. While providing a holistic approach to patient care this pleiotropy needs to be analyzed and systematized to enhance the efficacy and safety of the combination of them with APs. Guidelines for this type of treatment are still needed. In this review, we explore the pharmacological properties, therapeutic applications, and limitations of APs, and discuss the potential benefits and limitations of those dietary interventions that are employed to improve the efficacy and counteract side effects of APs discussing also their mechanisms of action. Finally, we critically discuss the main results of clinical studies combining APs and dietary interventions and provide a view on future directions in terms of research and clinical use of these combinations. Significance Statement: Antipsychotic drugs are useful in a variety of psychiatric conditions, yet their use is hampered by issues of efficacy and safety. An important step toward therapy optimization is their use in combination with dietary interventions (ie, dietary supplements and nutraceuticals) that have shown promising results in clinical trials.