Risperidone: a review of its use in the treatment of irritability associated with autistic disorder in children and adolescents

A Study of Microemulsion Systems for Transdermal Delivery of Risperidone Using Penetration Enhancers

The aim of this study was to develop and characterize microemulsion formulations using penetration enhancers as potential transdermal delivery systems for risperidone. Initially, a simple formulation of risperidone in Propylene Glycol (PG) was prepared as a control formulation, together with formulations incorporating various penetration enhancers, alone and/or in combination, and also microemulsion formulations with various chemical penetration enhancers, were prepared and all were evaluated for risperidone transdermal delivery. An ex-vivo permeation study was carried out using human cadaver skin and vertical glass Franz diffusion cells to compare all the microemulsion formulations. The microemulsion prepared from oleic acid as the oil (15%), Tween 80 (15%) as the surfactant and isopropyl alcohol (20%) as the co-surfactant, and water (50%) showed higher permeation with a flux value of 32.50±3.60 ug/hr/sq.cm, a globule size of 2.96±0.01 nm, a polydispersity index of 0.33±0.02 and pH of 4.95. This novel in vitro research disclosed that an optimized microemulsion formulated using penetration enhancers was able to increase permeation of risperidone by 14-fold compared to the control formulation. The data suggested that microemulsions may be useful in the delivery of risperidone via the transdermal route.

Risperidone impedes glutamate excitotoxicity in a valproic acid rat model of autism: Role of ADAR2 in AMPA GluA2 RNA editing

Several reports indicate a plausible role of calcium (Ca2+) permeable AMPA glutamate receptors (with RNA hypo-editing at the GluA2 Q/R site) and the subsequent excitotoxicity-mediated neuronal death in the pathogenesis of a wide array of neurological disorders including autism spectrum disorder (ASD). This study was designed to examine the effects of chronic risperidone treatment on the expression of adenosine deaminase acting on RNA 2 (Adar2), the status of AMPA glutamate receptor GluA2 editing, and its effects on oxidative/nitrosative stress and excitotoxicity-mediated neuronal death in the prenatal valproic acid (VPA) rat model of ASD. Prenatal VPA exposure was associated with autistic-like behaviors accompanied by an increase in the apoptotic marker "caspase-3" and a decrease in the antiapoptotic marker "BCL2" alongside a reduction in the Adar2 relative gene expression and an increase in GluA2 Q:R ratio in the hippocampus and the prefrontal cortex. Risperidone, at doses of 1 and 3 mg, improved the VPA-induced behavioral deficits and enhanced the Adar2 relative gene expression and the subsequent GluA2 subunit editing. This was reflected on the cellular level where risperidone impeded VPA-induced oxidative/nitrosative stress and neurodegenerative changes. In conclusion, the present study confirms a possible role for Adar2 downregulation and the subsequent hypo-editing of the GluA2 subunit in the pathophysiology of the prenatal VPA rat model of autism and highlights the favorable effect of risperidone on reversing the RNA editing machinery deficits, giving insights into a new possible mechanism of risperidone in autism.

Saliva based diagnostic methodologies for a fast track detection of autism spectrum disorder: A mini-review

Autism spectrum disorder (ASD) is considered a complicated neurodevelopment disorder with rising prevalence globally. ASD is characterized by a series of events including varying degrees of defects in communication, learning, and social interaction which is accompanied by stereotypical behavioral patterns. Despite extensive research, the current diagnosis for ASD is complex and almost solely based on the behavioral assessments of the suspected individuals. The multifactorial etiopathology of this disease along with the diversity of symptoms among different individuals adds to the current intricacies for accurate prognosis of ASD. Hence, there exists a dire need for biologically relevant biomarkers for an early diagnosis and for tracking the efficacy of therapeutic interventions. Until recently, among various biofluids, saliva has gained increasing interest for biomarker identification, the advantages include the non-invasive nature and ease of sample handling. This mini-review aims to provide a succinct summary of recent literature on saliva-based diagnostic modalities for ASD, examine various studies that highlight the potential use of proteomic and/or RNA-based biomarkers. Finally, some conclusive perspectives of using the salivary system for ASD mechanistic details and diagnosis are also discussed.

Practitioner's review: medication for children and adolescents with autism spectrum disorder (ASD) and comorbid conditions

Alleviating the multiple problems of children with autism spectrum disorder (ASD) and its comorbid conditions presents major challenges for the affected children, parents, and therapists. Because of a complex psychopathology, structured therapy and parent training are not always sufficient, especially for those patients with intellectual disability (ID) and multiple comorbidities. Moreover, structured therapy is not available for a large number of patients, and pharmacological support is often needed, especially in those children with additional attention deficit/hyperactivity and oppositional defiant, conduct, and sleep disorders.

Effects of Risperidone in Autistic Children and Young Adults: A Systematic Review and Meta-Analysis

There are several studies investigating the effects of risperidone on autism, but many of these studies are contradictory or inconclusive. This systematic review and meta-analysis investigated the effects of risperidone on five domains of the Aberrant Behaviour Checklist (ABC) scale on Autism Spectrum Disorder (ASD), as well as weight gain and waist circumference. The protocol for the present systematic review and meta-analysis was registered on the International Prospective Register of Systematic Reviews (PROSPERO). For this study, we analysed articles (2,459), selecting them according to the PICOS strategy (Population, Intervention, Comparison, Outcome, Study design). Although risperidone is effective for the treatment of lethargy and inadequate speech, concerns about the association between weight gain, waist circumference and risperidone require a need for evaluation of the risk-benefit ratio in its use. There was a significant association between weight gain, waist circumference and risperidone. In conclusion, it was possible to suggest the efficacy of risperidone for the treatment of lethargy and inadequate speech. Finally, we emphasize that the risk-benefit in its use should be evaluated (Protocol number CRD42019122316).

UGT1A1 polymorphisms associated with prolactin response in risperidone-treated children and adolescents with autism spectrum disorder

The aim of this study was to investigate the association of drug-metabolizing enzyme and transporter (DMET) polymorphisms with the risperidone-induced prolactin response using an overlapping gene model between serum prolactin level and hyperprolactinemia in autism spectrum disorder (ASD) patients. Eighty-four ASD patients who were receiving risperidone for at least 1 month were recruited and then assigned to either the normal prolactin group or the hyperprolactinemia group based on their serum prolactin level. The genotype profile of 1936 (1931 single nucleotide polymorphisms (SNPs) and 5 copy number variation (CNVs) drug metabolism markers was obtained using the Affymetrix DMET Plus GeneChip microarray platform. Genotypes of SNPs used to test the accuracy of DMET genotype profiling were determined using TaqMan SNP Genotyping Assay kits. Eighty-four patients were selected for the allelic association study after microarray analyses (51 in the normal prolactin group, and 33 in the hyperprolactinemia group). An overlapping allelic association analysis of both analyses discovered five DMET SNPs with a suggestive association (P < 0.05) with risperidone-induced prolactin response. Three UGT1A1 SNPs (UGT1A1*80c.-364C > T, UGT1A1*93 c.-3156G > A, and UGT1A1 c.-2950A > G, showed a suggestive association with the risperidone-induced prolactin response and found to be in complete linkage disequilibrium (D' value of 1). In this DMET microarray platform, we found three UGT1A1 variants with suggestive evidences of association with the risperidone-induced prolactin response both measured by hyperprolactinemia and by prolactin level. However, due to the lack of validation studies confirmation and further exploration are needed in future pharmacogenomic studies.

Prescription Trends of Psychotropics in Children and Adolescents with Autism Based on Nationwide Health Insurance Data

Children with autism are often medicated to manage emotional and behavioral symptoms; yet, data on such pharmacotherapy is insufficient. In this study, we investigated the Korean National Health Insurance Claims Database (NHICD) information related to autism incidence and psychotropic medication use. From the 2010-2012 NHICD, we selected a total of 31,919,732 subjects under 19 years old. To examine the diagnostic incidence, we selected patients who had at least one medical claim containing an 10th revision of International Statistical Classification of Diseases and Related Health Problems (ICD-10) code for pervasive developmental disorder, F84, not diagnosed in the previous 360 days. Psychotropics were categorized into seven classes. Then, we analyzed the data to determine the mean annual diagnostic incidence and psychotropic prescription trends. Diagnostic incidence was 17,606 for the 3 years, with a mean annual incidence per 10,000 population of 5.52. Among them, 5,348 patients were prescribed psychotropics. Atypical antipsychotics were the most commonly used, followed by antidepressants. An older age, male sex, and the availability of medical aid were associated with a higher rate of prescription than observed for a younger age, female sex, and the availability of health insurance. Psychotropic drugs were used for less than one-third of patients newly diagnosed with autism, and prescription differed by sex and age. Increased diagnostic incidence is associated with an increased prescription of psychotropic drugs. Therefore, medication-related safety data and policies for psychotropic drugs in autism should be prepared.

Comparative two-dimensional polyacrylamide gel electrophoresis of the salivary proteome of children with autism spectrum disorder

In the last decades, prevalence of autism spectrum disorder (ASD) has been on the rise. However, clear aetiology is still elusive and improvements in early diagnosis are needed. To uncover possible biomarkers present in ASD, we used two-dimensional polyacrylamide gel electrophoresis and nanoliquid chromatography-tandem mass spectrometry (nanoLC-MS/MS), to compare salivary proteome profiling of children with ASD and controls. A total of 889 spots were compared and only those spots with a fold change ≥1.7 and a P-value <0.05 or a fold change of ≥3.0 between ASD cases and controls were analysed by nanoLC-MS/MS. Alpha-amylase, CREB-binding protein, p532, Transferrin, Zn alpha2 glycoprotein, Zymogen granule protein 16, cystatin D and plasminogen were down-regulated in ASD. Increased expression of proto-oncogene Frequently rearranged in advanced T-cell lymphomas 1 (FRAT1), Kinesin family member 14, Integrin alpha6 subunit, growth hormone regulated TBC protein 1, parotid secretory protein, Prolactin-inducible protein precursor, Mucin-16, Ca binding protein migration inhibitory factor-related protein 14 (MRP14) was observed in individuals with ASD. Many of the identified proteins have previously been linked to ASD or were proposed as risk factors of ASD at the genetic level. Some others are involved in pathological pathways implicated in ASD causality such as oxidative stress, lipid and cholesterol metabolism, immune system disturbances and inflammation. These data could contribute to protein signatures for ASD presence, risk and subtypes, and advance understanding of ASD cause as well as provide novel treatment targets for ASD.

Sleep in Autism Spectrum Disorders

Autism spectrum disorders (ASD) are common neurodevelopmental conditions, affecting 1 in 68 children. Sleep disturbance, particularly insomnia, is very common in children diagnosed with ASD, with evidence supporting overlapping neurobiological and genetic underpinnings. Disturbed sleep exacerbates core and related ASD symptoms and has a substantial negative impact on the entire family. Treatment of sleep disturbance holds promise for ameliorating many of the challenging behavioral symptoms that children with ASD and their families face. Behavioral and pharmacological studies indicate promising approaches to treating sleep disturbances in this population. Awareness of treatment options is particularly important as parents and clinicians may believe that sleep disturbance is part of autism and refractory to therapy. In addition, autism symptoms refractory to treatment with conventional psychiatric medications may improve when sleep is addressed. Additional evidence-based studies are needed, including those that address the underlying biology of this condition.

A head-to-head comparison of aripiprazole and risperidone for safety and treating autistic disorders, a randomized double blind clinical trial

Aripiprazole and risperidone are the only FDA approved medications for treating irritability in autistic disorder, however there are no head-to-head data comparing these agents. This is the first prospective randomized clinical trial comparing the safety and efficacy of these two medications in patients with autism spectrum disorders. Fifty nine children and adolescents with autism spectrum disorders were randomized to receive either aripiprazole or risperidone for 2 months. The primary outcome measure was change in Aberrant Behavior Checklist (ABC) scores. Adverse events were assessed. Aripiprazole as well as risperidone lowered ABC scores during 2 months. The rates of adverse effects were not significantly different between the two groups. The safety and efficacy of aripiprazole (mean dose 5.5 mg/day) and risperidone (mean dose 1.12 mg/day) were comparable. The choice between these two medications should be on the basis of clinical equipoise considering the patient's preference and clinical profile.

Impairment of social behavior and communication in mice lacking the Uba6-dependent ubiquitin activation system

The Uba6-Use1 ubiquitin enzyme cascade is a poorly understood arm of the ubiquitin-proteasome system required for mouse development. Recently, we reported that Uba6 brain-specific knockout (termed NKO) mice display abnormal social behavior and neuronal development due to a decreased spine density and accumulation of Ube3a and Shank3. To better characterize a potential role for NKO mice in autism spectrum disorders (ASDs), we performed a comprehensive behavioral characterization of the social behavior and communication of NKO mice. Our behavioral results confirmed that NKO mice display social impairments, as indicated by fewer vocalizations and decreased social interaction. We conclude that UBA6 NKO mice represent a novel ASD mouse model of anti-social and less verbal behavioral symptoms.

Clinical and pharmacokinetic evaluation of risperidone for the management of autism spectrum disorder

INTRODUCTION

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is often accompanied by psychiatric comorbidity. Although there is no medication currently available to treat the core symptoms of ASD, risperidone was the first drug to be approved for use in ASD and is still the best established psychopharmacological option for the treatment of irritability and behavioral problems in ASD.

AREAS COVERED

This article gives an overview of the pharmacokinetic profile of risperidone and a comprehensive review of treatment studies regarding the use of risperidone in ASD.

EXPERT OPINION

Ample evidence supports the short-term use of risperidone for treating irritability and behavioral problems in ASD. Risperidone also shows promise in treating symptoms often associated with ASD, such as stereotypical behavior, social difficulties, hyperactivity and cognitive problems. However, several adverse effects have been identified; most are mild or moderate and well manageable, but weight gain and metabolic changes are a considerable concern. Therefore, risperidone should in our view be seen as 'a last resort', only justified for the short-term treatment of serious behavioral problems, which have failed to respond sufficiently to behavioral interventions. Future studies should investigate long-term effects of risperidone and factors that facilitate individual risk-benefit analyses before treatment.

Risperidone and the 5-HT2A receptor antagonist M100907 improve probabilistic reversal learning in BTBR T + tf/J mice

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interactions with restricted interests and repetitive behaviors (RRBs). RRBs can severely limit daily living and be particularly stressful to family members. To date, there are limited options for treating this feature in ASD. Risperidone, an atypical antipsychotic, is approved to treat irritability in ASD, but less is known about whether it is effective in treating "higher order" RRBs, for example cognitive inflexibility. Risperidone also has multiple receptor targets in which only a subset may be procognitive and others induce cognitive impairment. 5HT2A receptor blockade represents one promising and more targeted approach, as various preclinical studies have shown that 5HT2A receptor antagonists improve cognition. The present study investigated whether risperidone and/or M100907, a 5HT2A receptor antagonist, improved probabilistic reversal learning performance in the BTBR T + tf/J (BTBR) mouse model of autism. The effects of these treatments were also investigated in C57BL/6J (B6) mice as a comparison strain. Using a spatial reversal learning test with 80/20 probabilistic feedback, similar to one in which ASD individuals exhibit impairments, both risperidone (0.125 mg) and M100907 (0.01 and 0.1 mg) improved reversal learning in BTBR mice. Risperidone (0.125 mg) impaired reversal learning in B6 mice. Improvement in probabilistic reversal learning performance resulted from treatments enhancing the maintenance of the newly correct choice pattern. Because risperidone can lead to unwanted side effects, treatment with a specific 5HT2A receptor antagonist may improve cognitive flexibility in individuals with ASD while also minimizing unwanted side effects.

Efficacy and tolerability of pharmacotherapy options for the treatment of irritability in autistic children

Children with autism have a high rate of irritability and aggressive symptoms. Irritability or self-injurious behavior can result in significant harm to those affected, as well as to marked distress for their families. This paper provides a literature review regarding the efficacy and tolerability of pharmacotherapy for the treatment of irritability in autistic children. Although antipsychotics have not yet been approved for the treatment of autistic children by many countries, they are often used to reduce symptoms of behavioral problems, including irritability, aggression, hyperactivity, and panic. However, among antipsychotics, the Food and Drug Administration has approved only risperidone and aripiprazole to treat irritability in autism. Among atypical antipsychotics, olanzapine and quetiapine are limited in their use for autism spectrum disorders in children because of high incidences of weight gain and sedation. In comparison, aripiprazole and ziprasidone cause less weight gain and sedation. However, potential QTc interval prolongation with ziprasidone has been reported. Contrary to ziprasidone, no changes were evident in the QT interval in any of the trials for aripiprazole. However, head-to-head comparison studies are needed to support that aripiprazole may be a promising drug that can be used to treat irritability in autistic children. On the other hand, risperidone has the greatest amount of evidence supporting it, including randomized controlled trials; thus, its efficacy and tolerability has been established in comparison with other agents. Further studies with risperidone as a control drug are needed.

The effect of bumetanide treatment on the sensory behaviours of a young girl with Asperger syndrome

Sensory behaviours were not considered as core features of autism spectrum disorders until recently. However, they constitute an important part of the observed symptoms that result in social maladjustment and are currently quite difficult to treat. One promising strategy for the treatment of these behaviours is the use of bumetanide, which was previously shown to reduce the severity of autism spectrum disorders. In this study, we proposed to evaluate sensory behaviours using Dunn's Sensory Profile after 18 months of bumetanide treatment in a 10-year-old girl with Asperger syndrome. Reported improvements covered a large range of sensory behaviours, including auditory, vestibular, tactile, multisensory and oral sensory processing. Although our results were limited to a single case report, we believe that our clinical observations warrant clinical trials to test the long-term efficacy of bumetanide to manage the sensory behaviours of people with autism spectrum disorders.

The use of medications approved for Alzheimer's disease in autism spectrum disorder: a systematic review

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects 1 in 68 children in the United States. Even though it is a common disorder, only two medications (risperidone and aripiprazole) are approved by the U.S. Food and Drug Administration (FDA) to treat symptoms associated with ASD. However, these medications are approved to treat irritability, which is not a core symptom of ASD. A number of novel medications, which have not been approved by the FDA to treat ASD have been used off-label in some studies to treat ASD symptoms, including medications approved for Alzheimer's disease. Interestingly, some of these studies are high-quality, double-blind, placebo-controlled (DBPC) studies. This article systematically reviews studies published through April, 2014, which examined the use of Alzheimer's medications in ASD, including donepezil (seven studies, two were DBPC, five out of seven reported improvements), galantamine (four studies, two were DBPC, all reported improvements), rivastigmine (one study reporting improvements), tacrine (one study reporting improvements), and memantine (nine studies, one was DBPC, eight reported improvements). An evidence-based scale was used to rank each medication. Collectively, these studies reported improvements in expressive language and communication, receptive language, social interaction, irritability, hyperactivity, attention, eye contact, emotional lability, repetitive or self-stimulatory behaviors, motor planning, disruptive behaviors, obsessive-compulsive symptoms, lethargy, overall ASD behaviors, and increased REM sleep. Reported side effects are reviewed and include irritability, gastrointestinal problems, verbal or behavioral regression, headaches, irritability, rash, tremor, sedation, vomiting, and speech problems. Both galantamine and memantine had sufficient evidence ranking for improving both core and associated symptoms of ASD. Given the lack of medications approved to treat ASD, further studies on novel medications, including Alzheimer's disease medications, are needed.

Pharmacotherapy for the core symptoms in autistic disorder: current status of the research

The current review covers extant literature on pharmacotherapy for core symptoms of autism. The core symptoms of autism include impairments in social interaction and communication, as well as the presence of restricted and repetitive behaviors. There are no known efficacious treatments for the core social symptoms, although effects on repetitive behaviors are indicated with some data. While studies of fenfluramine, secretin, opiates, and mood stabilizers generally find no effect, mixed results suggest more research is needed on antidepressants and atypical antipsychotics. Newer lines of research, including cholinergic and glutamatergic agents and oxytocin, will be of considerable interest in the future. However, research on the treatment of core symptoms is plagued by limitations in study design, statistical power, and other issues inherent to the study of treatments for autism (e.g., heterogeneity of the disorder) that continue to prevent the elucidation of efficacious treatments.

Safety and pharmacokinetics of atypical antipsychotics in children and adolescents

Pediatric behavioral and affective disorders often require antipsychotic therapy, in combination with psychotherapeutic interventions, for their treatment and stabilization. Although pharmacotherapy can include either typical or atypical antipsychotics, the latter are generally preferred because of their apparently lower risk of adverse effects. Recent controlled trials have demonstrated the efficacy of some of these agents (including aripiprazole, clozapine, olanzapine, paliperidone, quetiapine, risperidone, ziprasidone) in adolescent schizophrenia and children or adolescent bipolar mania, or to treat severe aggression and self-injury in the context of autism in children and adolescents. Although few studies have systematically monitored their short- and, more importantly, long-term safety, current evidence indicates that sedation, hyperprolactinemia, and metabolic abnormalities such as excess weight gain, diabetes, and related cardiovascular effects were clinically relevant adverse effects in young patients, with the individual agents differing in their propensity to induce these effects. When prescribing antipsychotics for children and adolescents, physicians should therefore be aware of the specific adverse effect profiles and patients should be closely monitored for the short- and long-term development of adverse events. In pediatric patients, the starting dose, titration plan, and maintenance dose of antipsychotics must be based on their pharmacokinetics and metabolism, as in adults. Because there are significant individual differences in drug and active metabolite(s) pharmacokinetics and metabolism, which may be further affected by a number of confounding factors (including demographic variables, phenotype and drug interactions), therapeutic drug monitoring may be a valid tool for individualizing dosage, but its interpretation should also take account of changes in pharmacodynamic sensitivity with the development during childhood and adolescence.

Focal brain inflammation and autism

Increasing evidence indicates that brain inflammation is involved in the pathogenesis of neuropsychiatric diseases. Autism spectrum disorders (ASD) are characterized by social and learning disabilities that affect as many as 1/80 children in the USA. There is still no definitive pathogenesis or reliable biomarkers for ASD, thus significantly curtailing the development of effective therapies. Many children with ASD regress at about age 3 years, often after a specific event such as reaction to vaccination, infection, stress or trauma implying some epigenetic triggers, and may constitute a distinct phenotype. ASD children respond disproportionally to stress and are also affected by food and skin allergies. Corticotropin-releasing hormone (CRH) is secreted under stress and together with neurotensin (NT) stimulates mast cells and microglia resulting in focal brain inflammation and neurotoxicity. NT is significantly increased in serum of ASD children along with mitochondrial DNA (mtDNA). NT stimulates mast cell secretion of mtDNA that is misconstrued as an innate pathogen triggering an auto-inflammatory response. The phosphatase and tensin homolog (PTEN) gene mutation, associated with the higher risk of ASD, which leads to hyper-active mammalian target of rapamycin (mTOR) signalling that is crucial for cellular homeostasis. CRH, NT and environmental triggers could hyperstimulate the already activated mTOR, as well as stimulate mast cell and microglia activation and proliferation. The natural flavonoid luteolin inhibits mTOR, mast cells and microglia and could have a significant benefit in ASD.

In utero exposure to valproic acid and autism--a current review of clinical and animal studies

Valproic acid (VPA) is both an anti-convulsant and a mood stabilizer. Clinical studies over the past 40 years have shown that exposure to VPA in utero is associated with birth defects, cognitive deficits, and increased risk of autism. Two recent FDA warnings related to use of VPA in pregnancy emphasize the need to reevaluate its use clinically during child-bearing years. The emerging clinical evidence showing a link between VPA exposure and both cognitive function and risk of autism brings to the forefront the importance of understanding how VPA exposure influences neurodevelopment. In the past 10 years, animal studies have investigated anatomical, behavioral, molecular, and physiological outcomes related to in utero VPA exposure. Behavioral studies show that VPA exposure in both rats and mice leads to autistic-like behaviors in the offspring, including social behavior deficits, increased repetitive behaviors, and deficits in communication. Based on this work VPA maternal challenge in rodents has been proposed as an animal model to study autism. This model has both face and construct validity; however, like all animal models there are limitations to its translation to the clinical setting. Here we provide a review of clinical studies that examined pregnancy outcomes of VPA use as well as the related animal studies.

Treatment strategies for dosing the second generation antipsychotics

BACKGROUND

The second generation antipsychotics now have clinical approvals for the treatment of schizophrenia, bipolar depression, bipolar mania, autism, major depressive disorder and are used furthermore off-label to treat other mental disorders. Each agent is unique in its pharmacodynamic profile and allows for unique dosing strategies to be employed when treating these different disorders.

AIMS

To review relevant data regarding the second generation antipsychotics and their empirical dosing strategies. To further review and comment theoretically in these areas where substantial, definitive data are lacking.

MATERIALS AND METHODS

A MEDLINE and recent textbook review was conducted regarding each second generation antipsychotic and cross-referenced with searches for major mental disorders. The findings are compiled in the review below.

DISCUSSION

The second generation antipsychotics are clearly delineated in the treatment of psychosis and mania and share similar mechanisms of action to achieve these results: dopamine-2 receptor antagonism for efficacy and serotonin-2a receptor antagonism for EPS tolerability. From here, each agent has a unique pharmacodynamic and pharmacokinetic profile where some agents carry more, or less antidepressant, anxiolyic, or hypnotic profiles. Choosing an agent, and dosing it in low, middle, or high ranges may result in differential effectiveness and tolerability.

CONCLUSION

The second generation antipsychotics have many clinical applications in psychiatric practice. This article serves to review this and also suggests ways clinicians may optimize treatment based upon patient diagnosis and utilizing appropriate dosing of each individual second generation antipsychotic.

A dental look at the autistic patient through orofacial pain

Abstract Autism is a neurodevelopmental disorder characterized by impaired social interaction and restricted interests, compromised communication skills, and repetitive patterns of behavior. Both social and behavioral problems, which may include hyperactivity and quick frustration, may hinder the detection of other important pathologies such as orofacial pain. This is aggravated by the invasive nature of oral exploration, which may trigger violent and self-injurious responses, such as temper tantrums and/or head banging, which make the work of professionals extremely difficult during diagnoses, follow-up examinations, and dental treatments. In addition, mercury-containing amalgams used to treat dental caries (the most common form of acute orofacial pain) have been associated with higher rates of severe autism in children. The purpose of this review is to describe the current state of the art regarding the co-occurrence of orofacial pain and autism spectrum disorder, and how these conditions may interrelate clinically and neurobiologically.

Autism: an emerging 'neuroimmune disorder' in search of therapy

BACKGROUND

Autism spectrum disorders (ASDs) are neurodevelopmental disorders characterized by difficulties in communication and by repetitive and stereotypic behaviors, as well as by social impairment, attention, cognitive, and learning defects. ASDs present in early childhood and their prevalence has increased significantly to 1/150 children. Despite a number of theories, the actual reasons for this increase are still not clear. There is no reliable screening test, and no definite pathogenesis or curative therapy. Consequently, there is a major gap hampering development of effective treatments.

OBJECTIVE

To review recent publications on ASDs pathogenesis and treatment with emphasis on neuroimmune processes and new therapeutic approaches.

METHODS

Mostly original papers (450) on epidemiology, possible pathogenesis or treatment of ASDs in Medline from 1990 to May 2009 were reviewed. All authors contributed to this review.

RESULTS/CONCLUSION

Increased oxidative stress and immune dysregulation are present in ASDs. Mast-cell activation may contribute to gut-blood-brain barrier disruption and brain inflammation. No effective treatments have emerged. Well-designed clinical trials with nonpsychotropic drugs were few and ASD characteristics varied considerably, making conclusions difficult. Psychotropic drugs are often used for stereotypic and aggressive behaviors. Unique combinations with antioxidant and anti-inflammatory flavonoids hold promise. New potential translational research areas and possible treatments are suggested.

May the best friend be an enemy if not recognized early: possible role of omega-3 against cardiovascular abnormalities due antipsychotics in the treatment of autism

Autism spectrum disorders (ASD) are neurodevelopment disorders that cause severe and pervasive impairment in socialization, communication, and behavior. Although the availability of antipsychotic treatment in ASD has expanded, we will be very careful with side effects of these pharmacological agents. Following this reasoning, emerging data indicate that some antipsychotics may be associated with cardiovascular adverse events (e.g., QT interval prolongation), suggesting that this could be correlated to sudden death. Quite interesting, substantial evidence from epidemiological and case-control studies indicates that omega-3 reduces the risk of cardiovascular mortality, particularly sudden cardiac death. In accordance to the above mentioned findings, as omega-3 fatty acids per se have a direct cardiovascular protective role, our paper hypothesized that omega-3 fatty acids supplementation in ASD patients treated with atypical antipsychotic drugs may reduce cardiac arrhythmias and hence sudden cardiac death.

Paliperidone suppresses the development of the aggressive phenotype in a developmentally sensitive animal model of escalated aggression

RATIONALE

Atypical antipsychotics are commonly prescribed to clinically referred youngsters for treatment of heightened aggressive behavior associated with various psychiatric disorders. Previously, we demonstrated risperidone's anti-aggressive effects using a well-validated animal model of offensive aggression. Paliperidone, the main active metabolite of risperidone, is a potent serotonin-2A and dopamine-2 receptor antagonist with slightly different pharmacodynamic properties compared to risperidone. Given that much of risperidone's therapeutic efficacy is due to its active metabolite, paliperidone may effectively suppress aggression with fewer adverse side effects.

OBJECTIVES

Investigate whether paliperidone administration would reduce heightened aggressive behavior induced by low-dose cocaine exposure in a developmentally sensitive model of offensive aggression.

MATERIALS AND METHODS

Male Syrian hamsters (n = 12/group) were administered an acute dose of paliperidone (0.05, 0.1, 0.2, and 0.3 mg/kg) and then tested for aggressive behavior using the resident-intruder paradigm. To investigate the effects of chronic paliperidone administration, a separate set of animals (n = 12/group) was exposed to repeated paliperidone administration (0.1 mg kg(-1) day(-1)) during different developmental periods and varying lengths of time (1-4 weeks).

RESULTS

Experiment 1 results revealed a dose-dependent decrease in bite and attack behaviors with an effective dose observed at 0.1 mg/kg. In Experiment 2, the maximal reduction in aggressive behavior in response to chronic paliperidone treatment was observed in animals treated during the third week of adolescence, and this reduction occurred without concomitant alterations in non-aggressive behaviors.

CONCLUSIONS

These results support the specific aggression-suppressing properties of paliperidone and the potential use of this compound in the treatment of maladaptive aggression in clinical settings.

Atypical neuroleptic risperidone modulates glial functions in C6 astroglial cells

Risperidone has demonstrated therapeutic advantages over conventional neuroleptics and offers a valuable emerging option for the treatment of social behavior associated with autistic disorder. Considering the putative involvement of astroglial cells in neuropsychiatric disorders, we investigated the effect of risperidone on parameters of astrocyte activity - glutamate uptake, glutamine synthetase (GS) activity and glutathione (GSH) levels. Risperidone was able to induce a significantly increase on glutamate uptake (32%); GS activity (15%); GSH levels (58%). These findings imply the perspectives for further investigations directed on astrocytes from different brain areas. Our present results suggest that risperidone might exert its neuroprotective effects against brain illness at least partially via modulation of astrocyte functions.

[Risperidone use in child and adolescent psychiatric patients]

In a plural and multidisciplinary process of care, it would be fruitful to ally complementary, pharmacologic and psychodynamic approaches. We have done a review of the literature on the effectiveness and the cautions for prescription of risperidone, a second generation antipsychotic drug. Risperidone has proved helpful in treating children and adolescents with autism spectrum, conduct and bipolar disorders, Tourette's syndrome, and schizophrenia. The principal side effects are sedation, weight gain, and metabolic disturbances. Extrapyramidal symptoms, QTc prolongation, and hyperprolactemia with clinical signs are infrequent and not clinically significant. The benefit/risk is clearly in favor of the prescription when it is accompanied with the precautions and with the adequate monitoring.

A review of recent reports on autism: 1000 studies published in 2007

From 1000 studies published in 2007 on all aspects of autism, those that reached clear conclusions or included quantitative data were selected for this review. Possible etiologies include elemental metals, especially the inconsistent evidence regarding mercury from the vaccine preservative thimerosal, not used after 2001, and chromosomes and genes with the conclusion that autism has a complex genetic architecture. Also, various parental conditions are considered, as are many different abnormalities in the central nervous system, especially underconnectivity within the cortex. Furthermore, deficiencies in mirror neurons have been proposed, leading to the "theory of mind" explanation that autistic children tend to disregard others. In addition, various global deficiencies, like an increase in inhibitory synaptic transmission, are proposed. Characteristics of these children include selective (inward) attention; underresponsiveness; stereotyped repetitive motor behavior; increased head size, weight, and height; various cognitive and communicative disorders; and also epilepsy. Therapy has emphasized risperidone, but some atypical antipsychotic medications have been helpful, as have robotic aids, massage, hyperbaric oxygen, and music. Nearly every conceivable problem that a child could have can be observed in these unfortunate children.

Effect of the atypical neuroleptic risperidone on morphology and S100B secretion in C6 astroglial lineage cells

We investigated the effect of the atypical neuroleptic risperidone on morphology and S100B secretion in C6 glioma cells, considering the putative involvement of astroglial cells in neuropsychiatric disorders. In the presence of high experimental doses of risperidone, C6 cells become stellate, with process-bearing cells and partial retraction of the cell body followed by detachment from the adhesion surface with practically no cell death. These results indicate that risperidone is able to interfere with C6 cell adhesion without toxic effects. RhoA activator LPA prevented the effects of risperidone on cell morphology. From 6 h risperidone induced a statistically significant increment of about 80% in S100B secretion. These data contribute to the proposal that glial cells are targets of risperidone, which could be involved in the therapeutic response of risperidone to improve autism symptoms.