Schizophrenia is a complex syndrome of unknown etiology and difficult to manage. Unconjugated bilirubin has been researched as a potential biological marker of this syndrome. The objective of this review article was to gather the studies published to date on the relationship between this molecule and schizophrenia. Broad inclusion criteria have been used (PRISMA) to include as many relevant studies as possible. Fourteen studies were selected: 3 analyzed the effects of unconjugated hyperbilirubinemia in animal models; 6 demonstrated an increased incidence of schizophrenia in patients with increased unconjugated bilirubin; 2 reported an increased incidence of the disease in patients with decreased unconjugated bilirubin; and 3 linked an increased incidence of schizophrenia with an increased excretion of the oxidative product of bilirubin, the so-called biopyrrins. Because of apparently contradictory reported results, the hypothesis that the relationship between schizophrenia and unconjugated bilirubin was not linear and that there was an inflammatory dysfunction explaining this was considered. The 2 most accepted models for the pathophysiology of schizophrenia are described, and the possible role of the molecule in each is clarified. The bilirubin buffer system and its role in antioxidant defense was explored. The average levels of unconjugated bilirubin in patients with schizophrenia, schizoaffective disorder, and bipolar disorder were also compared, having been hypothesized that these diseases could be different points of a same pathological spectrum. Finally, it was concluded that unconjugated bilirubin is a promising molecule that could be used as a possible biological marker for schizophrenia, and the necessity of subsequent efforts for its research was considered.

Binge eating disorder (BED) is the most common type of eating disorder. According to the most recent data available, the estimated lifetime prevalence of BED among US adults in the general population is 0.85% (men 0.42% and women 1.25%). Among psychiatric treatment populations, prevalence is several-fold higher. Although many people with BED are obese (BMI ≥ 30 kg/m2), roughly half are not. In the DSM-5, BED is defined by recurrent episodes of binge eating (eating in a discrete period of time, an amount of food larger than most people would eat in a similar amount of time under similar circumstances and a sense of lack of control over eating during the episode), occurring on average at least once a week for 3 months, and associated with marked distress. BED often goes unrecognized and thus untreated; in one study, 344 of 22,387 (1.5%) survey respondents met DSM-5 criteria for BED, but only 11 out of the 344 had ever been diagnosed with BED by a health-care provider. Psychiatric comorbidities are very common, with most adults with BED also experiencing anxiety disorders, mood disorders, impulse control disorders, or substance use disorders, suggesting that clinicians have patients in their practice with unrecognized BED. Multiple neurobiological explanations have been suggested for BED, including dysregulation in reward center and impulse control circuitry. Additionally, there is interplay between genetic influences and environmental stressors. Psychological treatments such as cognitive behavioral interventions have been recommended as first line and are supported by meta-analytic reviews; however, access to such treatments may be limited because of local availability and/or cost, and these treatments generally lead to little to no weight loss, although successfully eliminating binge eating can protect against future weight gain. Routine medication treatments for anxiety and depression do not necessarily ameliorate the symptoms of BED, but there are approved and emerging medication options, lisdexamfetamine and dasotraline, respectively, that specifically address the core drivers behind binge eating, namely obsessive thoughts and compulsive behaviors regarding food, resulting in marked decreases in binge eating behaviors as well as weight loss.

Although currently available antidepressants increase monoamine levels soon after the start of treatment, therapeutic benefits are often delayed by several weeks and the majority of patients with major depressive disorder fail to achieve an adequate response to first- or second-line therapies targeting monoamines. The recent approval of the NMDA (N-methyl-d-aspartate) antagonist esketamine given intranasally for treatment-resistant depression has reinforced the need for agents with rapid onset with alternate mechanisms of action. Dextromethorphan/bupropion, an investigational medicine currently in development, is one such candidate.

Pharmacotherapy of multiple sclerosis (MS) is evolving rapidly. Despite impressive gains over the past 2 decades in the approval of multiple drugs for MS, lack of recruitment of minorities with MS in phase 3 clinical studies is a persistent concern and skews efficacy and disability data.

Opioid use disorder (OUD) is a disorder that can lead to several negative outcomes, including overdose and death. A variety of opioids can be abused by individuals including both prescribed and non-prescribed opioids. Continued opioid use can be driven by negative affective states associated with opioid withdrawal. Several treatments exist in the field including medication assisted treatments such as methadone, buprenorphine, and naltrexone. Treatments such as clonidine and lofexidine can also be used to assist with decreasing withdrawal symptoms. Increasing adherence to treatment can further improve patient outcomes and promote continuation with treatment. A variety of methods to reduce relapse can also be utilized such as opioid agonists and maintenance therapy. According to the Centers for Disease Control, opioid overdoses contributed to 67.8% of overdose deaths in 2017.

Cognitive impairments reported across psychiatric conditions (ie, major depressive disorder, bipolar disorder, schizophrenia, and posttraumatic stress disorder) strongly impair the quality of life of patients and the recovery of those conditions. There is therefore a great need for consideration for cognitive dysfunction in the management of psychiatric disorders. The redundant pattern of cognitive impairments across such conditions suggests possible shared mechanisms potentially leading to their development. Here, we review for the first time the possible role of inflammation in cognitive dysfunctions across psychiatric disorders. Raised inflammatory processes (microglia activation and elevated cytokine levels) across diagnoses could therefore disrupt neurobiological mechanisms regulating cognition, including Hebbian and homeostatic plasticity, neurogenesis, neurotrophic factor, the HPA axis, and the kynurenine pathway. This redundant association between elevated inflammation and cognitive alterations across psychiatric disorders hence suggests that a cross-disorder approach using pharmacological and nonpharmacological (ie, physical activity and nutrition) anti-inflammatory/immunomodulatory strategies should be considered in the management of cognition in psychiatry.

With more long-acting injectable (LAI) antipsychotics available for treating schizophrenia, each with variable durations of action (2 weeks to 3 months), it is important to have clear management strategies for patients developing breakthrough psychotic symptoms or experiencing symptomatic worsening on LAIs. However, no treatment guidelines or clinical practice pathways exist; health-care providers must rely on their own clinical judgment to manage these patients. This article provides practical recommendations—based on a framework of clinical, pharmacokinetic, and dosing considerations—to guide clinicians’ decisions regarding management of breakthrough psychotic symptoms. Management options include ruling out/addressing medical illness or substance abuse/misuse as a contributing factor, addressing stressors, optimizing nonpharmacologic treatments, treating medical/psychiatric comorbidities, ensuring proper LAI administration technique, addressing missed LAI doses or lack of steady-state attainment, and increasing LAI dose directly or indirectly by shortening the injection interval (off-label). If these strategies do not work sufficiently with frequent monitoring, the LAI could be supplemented with a low dose of the corresponding oral formulation for fast symptom control (off-label). However, caution should be exercised with this strategy, because data on the safety of concomitant use of LAI and oral antipsychotics (OAPs) are limited, especially over extended periods. If symptoms abate, therapy optimization could be continued and slow discontinuation of the OAP could be considered. For persistent/worsening symptoms, the OAP should be increased to optimum effective dose while intensifying the initial steps used before it was added. If this fails, switching the OAP or LAI could be considered. We believe that these strategies will help clinicians manage breakthrough psychotic symptoms during LAI treatment and improve overall outcomes among those who can benefit from LAIs.

Approximately 20%–30% of schizophrenia patients are resistant to current standard pharmacotherapies. Recent schizophrenia research aims to identify specific pathophysiological abnormalities and novel targets in the disease, with the goals of identifying at-risk individuals, facilitating diagnosis, prompting early and personalized interventions, and helping predict response to treatment. Metabolomics involves the systematic study of the profile of biochemical alterations early in the course of a given disorder. Major aspects of the schizophrenia metabolome have been characterized, uncovering potential selective biomarkers for the disease that may change how the disorder is diagnosed, and how patients are stratified and treated. This review focuses on the most common metabolomic fingerprints of the different pathways involved in the pathophysiology of schizophrenia, and the potential development of novel metabolomic-related pharmacotherapies for improved treatment of schizophrenia and other related idiopathic psychotic disorders.