Possibilities and limitations of antidepressant use to correct depressive and negative symptoms in schizophrenia

Abstract
The purpose of this review is to analyze approaches to the treatment of depressive and negative disorders in schizophrenia in terms of their level of efficacy and safety. Materials and Methods: A search was conducted for full-text articles published over the last 10 years in PubMed, Springer, Wiley Online Library, Taylor & Francis Online, APA PsycInfo, CORE, Science Direct, and eLIBRARY.RU databases. Several articles published previously to this period were also included into the review due to their high scientific value. Results: Our review suggests that antidepressants (ADs) are effective medications and they can be prescribed to correct depressive disorders and negative symptoms in patients with schizophrenia when used in combination with antipsychotics (АPs). However, when administering ADs and АPs combinations, it is important to consider the safety profile of these combinations as well as their tolerance. Negative symptoms of schizophrenia, including those induced by a number of АP, are less amenable to correction by АDs monotherapy, which requires a long period of АPs (on average - 8 weeks), which can be limited in the real life of the patient outside the hospital. Current approaches to the therapy of depressive disorders in patients suffering from schizophrenia vary from country to country. However, most of АDs used in clinical psychiatric practice are widely used in the comorbid state under consideration. Conclusion: The efficacy and safety of АDs of the different classes considered in this review depends on their mechanisms of action, duration of admission, type of АPs taken, and specific clinical situation (acute depressive disorder, major depressive episode, or chronic depressive episode). Most promising in clinical practice are serotonin–norepinephrine reuptake inhibitors (SNRIs) and dual ADs. The use of tricyclic antidepressants (TCAs) is limited due to a higher risk of adverse drug reactions (ADRs). The use of most selective serotonin reuptake inhibitors (SSRIs) is limited due to the risk of aggravation of hallucinations (this risk being higher for patients with visual hallucinations, and lower for those with auditory hallucinations) and\or iatrogenic psychosis. These ADRs may probably occur in patients suffering from schizophrenia due to their ideal "poor metabolizer" pharmacogenetic profile, since most of the drugs considered in this review have hepatic metabolism.