Risperidone: a review of its use in the treatment of bipolar mania

3-Halo-5,6-dihydro-4H-1,2-oxazine N-oxides as synthetic equivalents of unsaturated nitrile oxides in the [3 + 2]-cycloaddition with arynes: synthesis of substituted 3-vinyl-1,2-benzisoxazoles

The reaction of 3-halo-5,6-dihydro-4H-1,2-oxazine N-oxides with arynes was studied. Arynes were generated from o-silylaryl triflates and underwent consecutive [3 + 2]-cycloaddition/[4 + 2]-cycloreversion with N-oxides leading to substituted 3-vinyl-benzisoxazoles in high yields. In the presented sequence, 1,2-oxazine N-oxides act as surrogates of rarely employed unsaturated nitrile oxides. A broad substrate scope was demonstrated. The influence of the substitution pattern of an aryne on the reaction outcome was determined. In the presence of bulky substituents, polycyclic 4,4a-dihydro-3H-benzofuro[3,2-c][1,2]oxazines were selectively formed. Mechanistic schemes for the observed reaction pathways were proposed. The synthetic utility of the products was demonstrated by their follow-up modifications.

Pharmacogenomics and non-genetic factors affecting drug response in autism spectrum disorder in Thai and other populations: current evidence and future implications

Autism spectrum disorder (ASD) may affect family and social life profoundly. Although there is no selective pharmacotherapy for ASD, the Food and Drug Administration (FDA) has recommended risperidone/aripiprazole to treat the associated symptoms of ASD, such as agitation/irritability. Strong associations of some pharmacokinetic/pharmacodynamic gene variants, e.g., CYP2D6 and DRD2, with risperidone-induced hyperprolactinemia have been found in children with ASD, but such strong genetic associations have not been found directly for aripiprazole in ASD. In addition to pharmacogenomic (PGx) factors, drug-drug interactions (DDIs) and possibly cumulative effects of DDIs and PGx may affect the safety or effectiveness of risperidone/aripiprazole, which should be assessed in future clinical studies in children with ASD. Reimbursement, knowledge, and education of healthcare professionals are the key obstacles preventing the successful implementation of ASD pharmacogenomics into routine clinical practice. The preparation of national and international PGx-based dosing guidelines for risperidone/aripiprazole based on robust evidence may advance precision medicine for ASD.

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.

Evaluation of antinociceptive effect and pharmacological mechanisms of thiocyanoacetamide in rats

OBJECTIVE

Acute pain is the most common type of pain. The aim of the present work was carried out to study the antinociceptive effect and pharmacological mechanisms of thiocyanoacetamide (Thm) in rats exposed to thermal pain stimulus.

MATERIALS AND METHODS

The anti-nociceptive effect of the newly synthesized compound, Thm was studied in comparison to that of paracetamol (Para), dexamethasone (Dex), and morphine (Morph) at different doses using a hot plate test at a constant temperature of 48.0 ± 0.5°C. During this test, the latency time (LT) was measured when rats express pain behavior. Then, the pharmacological mechanisms were determined using receptor-antagonist drugs.

RESULTS

Firstly, the obtained result showed pain modulation of the pretreated rats with Thm at 10 mg/kg dose proved by the delay of latency time during the thermal test. This significant antinociceptive activity of the thiocyanoacetamide was more effective than that of paracetamol or dexamethasone and less than that of morphine. Second, the pretreatment with acebutolol or risperidone antagonist drugs of, respectively, adrenergic and serotonin receptors demonstrated the elimination of pain modulation with Thm 10 mg/kg dose proved by a short latency time of rat's response in hot plate test. In this case, the pharmacological mechanism of Thm was characterized by the involvement of adrenergic and serotoninergic systems.

CONCLUSIONS

It may be concluded that Thm constitutes a promising antinociceptive drug including beta-adrenergic and serotoninergic targets. The present study warrants further investigation to determine the side effects of this compound.

CuI-catalyzed synthesis of multisubstituted pyrido[1,2-a]pyrimidin-4-ones through tandem Ullmann-type C-N cross-coupling and intramolecular amidation reaction

Various multi-substituted pyrido[1,2-a]pyrimidin-4-ones were synthesized via a one-pot tandem CuI-catalyzed C-N bond formation/intramolecular amidation reaction at 130 °C in DMF. This protocol features simple operation, broad substrate scope, good functional group tolerance and gram scale preparation, thus allowing practical and modular synthesis of pyrido[1,2-a]pyrimidin-4-ones from readily available 2-halopyridine and (Z)-3-amino-3-arylacrylate ester in good to excellent yields.

G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders

Neuropsychiatric disorders are multifactorial disorders with diverse aetiological factors. Identifying treatment targets is challenging because the diseases are resulting from heterogeneous biological, genetic, and environmental factors. Nevertheless, the increasing understanding of G protein-coupled receptor (GPCR) opens a new possibility in drug discovery. Harnessing our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective drugs. This review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric diseases. Besides, we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.

Mood Stabilizers of First and Second Generation

The topic of this narrative review is mood stabilizers. First, the author's definition of mood-stabilizing drugs is provided. Second, mood-stabilizing drugs meeting this definition that have been employed until now are described. They can be classified into two generations based on the chronology of their introduction into the psychiatric armamentarium. First-generation mood stabilizers (FGMSs), such as lithium, valproates, and carbamazepine, were introduced in the 1960s and 1970s. Second-generation mood stabilizers (SGMSs) started in 1995, with a discovery of the mood-stabilizing properties of clozapine. The SGMSs include atypical antipsychotics, such as clozapine, olanzapine, quetiapine, aripiprazole, and risperidone, as well as a new anticonvulsant drug, lamotrigine. Recently, as a candidate for SGMSs, a novel antipsychotic, lurasidone, has been suggested. Several other atypical antipsychotics, anticonvulsants, and memantine showed some usefulness in the treatment and prophylaxis of bipolar disorder; however, they do not fully meet the author's criteria for mood stabilizers. The article presents clinical experiences with mood stabilizers of the first and second generations and with "insufficient" ones. Further, current suggestions for their use in preventing recurrences of bipolar mood disorder are provided.

Electro-Oxidative C3-Selenylation of Pyrido[1,2-a]pyrimidin-4-ones

In this work, we achieved a C3-selenylation of pyrido[1,2-a]pyrimidin-4-ones using an electrochemically driven external oxidant-free strategy. Various structurally diverse seleno-substituted N-heterocycles were obtained in moderate to excellent yields. Through radical trapping experiments, GC-MS analysis and cyclic voltammetry study, a plausible mechanism for this selenylation was proposed.

Pharmacogenomics in clinical practice to prevent risperidone-induced hyperprolactinemia in autism spectrum disorder

Autism spectrum disorder (ASD) is a global challenge that may disrupts family and social life significantly. There is robust evidence for the association of a pharmacokinetic gene variant (e.g., CYP2D6) with risperidone-induced hyperprolactinemia in ASD. Association of a pharmacodynamic gene variant (e.g., DRD2) with risperidone-induced hyperprolactinemia in ASD is also evident from multiple studies. In addition to genetic factors, dose, duration and drug-drug interactions of risperidone might also increase the serum prolactin level. There are several difficulties, such as reimbursement, knowledge and education of healthcare providers, in implementing risperidone pharmacogenomics into clinical practice. However, preparation of national and international pharmacogenomics-based dosing guidelines of risperidone may advance precision medicine of ASD.

Alkynoates as Versatile and Powerful Chemical Tools for the Rapid Assembly of Diverse Heterocycles under Transition-Metal Catalysis: Recent Developments and Challenges

Heterocycles, heteroaromatics and spirocyclic entities are ubiquitous components of a wide plethora of synthetic drugs, biologically active natural products, marketed pharmaceuticals and agrochemical targets. Recognizing their high proportion in drugs and rich pharmacological potential, these invaluable structural motifs have garnered significant interest, thus enabling the development of efficient catalytic methodologies providing access to architecturally complex and diverse molecules with high atom-economy and low cost. These chemical processes not only allow the formation of diverse heterocycles but also utilize a range of flexible and easily accessible building units in a single operation to discover diversity-oriented synthetic approaches. Alkynoates are significantly important, diverse and powerful building blocks in organic chemistry due to their unique and inherent properties such as the electronic bias on carbon-carbon triple bonds posed by electron-withdrawing groups or the metallic coordination site provided by carbonyl groups. The present review highlights the comprehensive picture of the utility of alkynoates (2007-2019) for the synthesis of various heterocycles (> 50 types) using transition-metal catalysts (Ru, Rh, Pd, Ir, Ag, Au, Pt, Cu, Mn, Fe) in various forms. The valuable function of versatile alkynoates (bearing multifunctional groups) as simple and useful starting materials is explored, thus cyclizing with an array of coupling partners to deliver a broad range of oxygen-, nitrogen-, sulfur-containing heterocycles alongside fused-, and spiro-heterocyclic compounds. In addition, these examples will also focus the scope and reaction limitations, as well as mechanistic investigations into the synthesis of these heterocycles. The biological significance will also be discussed, citing relevant examples of drug molecules highlighting each class of heterocycles. This review summarizes the recent developments in the synthetic methods for the synthesis of various heterocycles using alkynoates as readily available starting materials under transition-metal catalysis.

Tf2O-Mediated Cyclization of α-Acyl-β-(2-aminopyridinyl)acrylamides: Access to N-Substituted 4H-Pyrido[1,2-a]pyrimidin-4-imines

A facile and efficient direct synthesis of N-substituted 4H-pyrido[1,2-a]pyrimidin-4-imines is developed from α-acyl-β-(2-aminopyridinyl)acrylamides mediated by triflic anhydride (Tf₂O) in the presence of 2-chloropyridine. This amide activation protocol features mild reaction conditions, simple execution, excellent yields, and high chemoselectivity, and is also applied to the synthesis of substituted 4H-pyrido[1,2-a]pyrimidin-4-ones via a practical one-pot procedure.

Palladium-catalyzed direct alkenylation of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-ones using oxygen as the oxidant

A direct C-3 alkenylation of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-ones through palladium-catalyzed C–H activation using oxygen as the terminal oxidant has been developed.

Heterogeneous Cu/OMS-2 as an efficient catalyst for the synthesis of tetrasubstituted 1,4-enediones and 4H-pyrido[1,2-a]-pyrimidin-4-ones

Copper supported on OMS-2: a heterogeneous catalyst Cu/OMS-2 was prepared for the synthesis of tetrasubstituted 1,4-enediones and 4H-pyrido[1,2-a]-pyrimidin-4-ones under the same conditions with air as the oxidant.

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 estimation of utility weights in cost-utility analysis for mental disorders: a systematic review

OBJECTIVE

To systematically review approaches and instruments used to derive utility weights in cost-utility analyses (CUAs) within the field of mental disorders and to identify factors that may have influenced the choice of the approach.

METHODS

We searched the databases DARE (Database of Abstracts of Reviews of Effects), NHS EED (National Health Service Economic Evaluation Database), HTA (Health Technology Assessment), and PubMed for CUAs. Studies were included if they were full economic evaluations and reported quality-adjusted life-years as the health outcome. Study characteristics and instruments used to estimate utility weights were described and a logistic regression analysis was conducted to identify factors associated with the choice of either the direct (e.g. standard gamble) or the preference-based measure (PBM) approach (e.g. EQ-5D).

RESULTS

We identified 227 CUAs with a maximum in 2009, 2010, and 2012. Most CUAs were conducted in depression, dementia, or psychosis, and came from the US or the UK, with the EQ-5D being the most frequently used instrument. The application of the direct approach was significantly associated with depression, psychosis, and model-based studies. The PBM approach was more likely to be used in recent studies, dementia, Europe, and empirical studies. Utility weights used in model-based studies were derived from only a small number of studies.

LIMITATIONS

We only searched four databases and did not evaluate the quality of the included studies.

CONCLUSIONS

Direct instruments and PBMs are used to elicit utility weights in CUAs with different frequencies regarding study type, mental disorder, and country.

Striatal structure and function in mood disorders: a comprehensive review

OBJECTIVES

  A large and diverse literature has implicated abnormalities of striatal structure and function in both unipolar and bipolar disorder. Recent functional imaging studies have greatly expanded this body of research. The aim of this review is to provide a comprehensive and critical appraisal of the relevant literature.

METHODS

  A total of 331 relevant articles were reviewed to develop an integrated overview of striatal function in mood disorders.

RESULTS

  There is compelling evidence from multiple studies that functional abnormalities of the striatum and greater corticostriatal circuitry exist in at least some forms of affective illness. The literature does not yet provide data to determine whether these aberrations represent primary pathology or they contribute directly to symptom expression. Finally, there is considerable evidence that bipolar disorder may be associated with striatal hyperactivity and some suggestion that unipolar illness may be associated with hypoactivation.

CONCLUSIONS

  Additional research investigating striatal function in affective disorders will be critical to the development of comprehensive models of the neurobiology of these conditions.

Risperidone long-acting injection: in bipolar I disorder

A long-acting intramuscular formulation of the atypical antipsychotic agent risperidone is now indicated for the maintenance treatment of patients with bipolar I disorder. The formulation utilizes a novel drug delivery system of biodegradable microspheres and is bioequivalent to the oral formulation of the drug. Moreover, fluctuations in plasma drug concentrations at steady state were 1.7-fold lower with long-acting than with oral risperidone. Maintenance treatment with risperidone long-acting injection, as monotherapy in adults with stabilized bipolar I disorder or as an adjunct to standard therapy in adults with stabilized, frequently relapsing bipolar I disorder, was effective in delaying relapse to symptoms in two well designed trials with maintenance phases of 1 or 2 years' duration. The time to relapse to any mood episode (primary endpoint) was significantly longer with risperidone long-acting injection than with placebo in both studies. Risperidone long-acting injection also significantly reduced the risk of relapse relative to placebo in these trials. Maintenance treatment with risperidone long-acting injection was generally well tolerated in patients with bipolar disorder, both as monotherapy and adjunctive therapy, with most adverse reactions being of mild to moderate severity.

Cross-species assessments of motor and exploratory behavior related to bipolar disorder

Alterations in exploratory behavior are a fundamental feature of bipolar mania, typically characterized as motor hyperactivity and increased goal-directed behavior in response to environmental cues. In contrast, abnormal exploration associated with schizophrenia and depression can manifest as prominent withdrawal, limited motor activity, and inattention to the environment. While motor abnormalities are cited frequently as clinical manifestations of these disorders, relatively few empirical studies have quantified human exploratory behavior. This article reviews the literature characterizing motor and exploratory behavior associated with bipolar disorder and genetic and pharmacological animal models of the illness. Despite sophisticated assessment of exploratory behavior in rodents, objective quantification of human motor activity has been limited primarily to actigraphy studies with poor cross-species translational value. Furthermore, symptoms that reflect the cardinal features of bipolar disorder have proven difficult to establish in putative animal models of this illness. Recently, however, novel tools such as the human behavioral pattern monitor provide multivariate translational measures of motor and exploratory activity, enabling improved understanding of the neurobiology underlying psychiatric disorders.

Functional SNPs in Genes Encoding the 5-HT2A Receptor Modify the Affinity and Potency of Several Atypical Antipsychotic Drugs

Atypical antipsychotic drugs (AADs) are the standard treatment for both the acute and long-term management of schizophrenia and an augmentation to mood stabilizers for bipolar disorder (BD). Yet many individuals who take AADs do not fully respond to them, while others experience side effects that include weight gain and metabolic disorder. This in vitro pharmacogenetic study examined whether allelic variants in the 5-hydroxytryptamine (HT)2A receptor alter the in vitro pharmacology of six AADs (clozapine, olanzapine, risperidone, quetiapine, ziprasidone, and aripiprazole). We selected 4 functional single-nucleotide polymorphisms (SNPs) for investigation (Thr25Asn, Ile197Val, Ala447Val, and His452Tyr), conducted site-directed mutagenesis studies to induce variants into human HEK-293 cell lines, and screened allelic variants for their effects on 5-HT 2A receptors in the cell lines. We conducted numerous binding assays and fluorescence-based assay system (FLEX station) experiments using the six AADs. Our results indicated that three polymorphic 5-HT2A receptors (Ile197Val, Ala447Val, and His452Tyr) exhibited statistically significant, though modest, changes in atypical antipsychotic affinity. In addition, three polymorphic receptors (Thr25Asn, Ile197Val, and His452Try) altered AAD potency. Our findings support in vivo evidence that functional SNPs in genes encoding neuroreceptor drug targets could explain interindividual differences in AAD drug response and tolerability. We suggest that more in vivo pharmacogenetic studies of well-characterized patients who are prescribed AADs be indicated. Future pharmacogenetic studies of well-characterized patients will likely involve tagging SNPs and the use of haplotypes related to other genes encoding neuroreceptor drug targets.

[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.

Spotlight on risperidone in irritability associated with autistic disorder in children and adolescents

Risperidone (Risperdal), a psychotropic atypical antipsychotic agent, is thought to act via dopamine D(2) and serotonin 5-HT(2A) receptor antagonism. The clinical efficacy of oral risperidone in the treatment of bipolar mania and schizophrenia in adult patients is well established. In the US, risperidone is also approved for the treatment of irritability associated with autistic disorder in children and adolescents aged 5-16 years, for the treatment of schizophrenia in adolescents aged 13-17 years and, as monotherapy, for the short-term treatment of acute manic and mixed episodes associated with bipolar I disorder in children and adolescents aged 10-17 years. Oral risperidone treatment was better than placebo treatment in reducing irritability and other behavioural symptoms associated with autistic disorder in children and adolescents in two well designed short-term trials, with these benefits maintained in those receiving risperidone for up to 6 months. The drug had a clinically manageable tolerability profile, with most adverse events being of mild to moderate intensity. There are some aspects of treatment, such as weight gain, somnolence and hyperglycaemia, that require monitoring, and the long-term safety of risperidone in children and adolescents with autistic disorder remains to be fully determined. With these issues in mind, risperidone offers a valuable emerging option for the treatment of irritability associated with autistic disorder in children and adolescents.

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

Risperidone (Risperdal), a psychotropic atypical antipsychotic agent, is thought to act via dopamine D(2) and serotonin (5-HT [5-hydroxytryptamine])(2A) receptor antagonism. The clinical efficacy of oral risperidone in the treatment of bipolar mania and schizophrenia in adult patients is well established. In the US, risperidone is also approved for the treatment of irritability associated with autistic disorder in children and adolescents aged 5-16 years, for the treatment of schizophrenia in adolescents aged 13-17 years and, as monotherapy, for the short-term treatment of acute manic and mixed episodes associated with bipolar I disorder in children and adolescents aged 10-17 years. Oral risperidone treatment was better than placebo treatment in reducing irritability and other behavioral symptoms associated with autistic disorder in children and adolescents in two well designed short-term trials, with these benefits maintained in those receiving risperidone for up to 6 months. The drug had a clinically manageable tolerability profile, with most adverse events being of mild to moderate intensity. There are some aspects of treatment, such as weight gain, somnolence, and hyperglycemia, that require monitoring, and the long-term safety of risperidone in children and adolescents with autistic disorder remains to be fully determined. With these issues in mind, risperidone offers a valuable emerging option for the treatment of irritability associated with autistic disorder in children and adolescents.

Role of risperidone in the treatment of bipolar disorder

Bipolar disorder is a serious illness, distinguished by marked variations in mood, energy and functional capability. The primary goals in the management of bipolar disorder are to treat acute episodes and to prevent recurrence. Many studies have demonstrated that atypical antipsychotic drugs can provide alternatives to traditional mood stabilizers in the treatment of this disorder. Risperidone is an atypical antipsychotic that is approved in the USA and in most European countries for use in bipolar mania or bipolar I disorder-manic/mixed episode. Preliminary data exist on the efficacy of risperidone in long-term treatment. However, randomized controlled trials are required to confirm the role of this agent in bipolar depression, and to validate efficacy as in the maintenance setting. This article focuses on the use of risperidone in the treatment of bipolar disorder, with an emphasis on randomized, placebo-controlled trials, and presents a brief overview of other atypical antipsychotic drugs. To conclude, we provide a perspective on the potential future role of risperidone in this disorder.

Use of psychotropic medications in treating mood disorders during lactation : practical recommendations

Many new mothers who need antidepressant or mood-stabilising drug treatment may wish to breastfeed their infants, but are hesitant to do so because of possible harmful effects of the medication on the infant. This article reviews current data on drug excretion into breast milk and the effects on the breast-fed child, and provides recommendations for the use of the different psychotropic drugs in lactating women. Relevant literature was identified through systematic searches of MEDLINE, EMBASE and the Science Citation Index Expanded (ISI) from 1966 to February 2005. The present knowledge is based on the accumulation of case studies. No randomised controlled trials in breast-fed infants have been performed and there is a lack of long-term follow-up studies. Use of SSRIs and TCAs (except doxepin) is compatible with breastfeeding. However, if treatment with an SSRI is started in the postpartum period, fluoxetine and citalopram may not be drugs of first choice. With regard to other antidepressants, such as venlafaxine, trazodone, mirtazapine, reboxetine, moclobemide and other MAOIs, very little knowledge exists. Breastfeeding should be avoided while using lithium. Carbamazepine and sodium valproate (valproic acid) are generally better tolerated by the breast-fed infant than lithium. Data on lamotrigine are still sparse. Knowledge is also scarce on the novel antipsychotics and thus recommendations in lactating women cannot be made for these agents. It is unwise to expose infants unnecessarily to drugs that may have severe adverse effects. As such, clozapine should probably be avoided because of the risk of agranulocytosis. Our knowledge of the impact of drug exposure through breast milk is still limited. Infant drug exposure is, however, generally higher during pregnancy through placental passage than through breast milk. Despite the low dosage transferred to the infant through breast milk, premature infants and infants with neonatal diseases or inherited disturbances in metabolism may be vulnerable to such exposure.

Risperidone in the treatment of bipolar mania

Atypical antipsychotic medications have assumed growing importance for the treatment of bipolar disorder, an illness that affects approximately 1.2%-3.7% of the general population in a given year. Current practice guidelines for the treatment of bipolar mania support the use of atypical antipsychotic medications as monotherapy or as a component of polytherapy, and in clinical settings the use of atypical antipsychotics to treat bipolar disorder is widespread. Risperidone is an atypical antipsychotic, sometimes referred to as a second-generation antipsychotic. The receptor-binding profile of risperidone, which includes potent antagonism of the serotonin 5-HT2(A), dopamine D(2), and alpha-adrenergic receptors, is believed to be related to positive effects on mood. The FDA-approved bipolar indications for risperidone include: 1) monotherapy for short-term treatment of acute manic or mixed episodes associated with bipolar I disorder and 2) combination therapy with lithium or valproate for the short-term treatment of acute manic or mixed episodes associated with bipolar I disorder. This review of risperidone for bipolar mania will address the chemistry, pharmacodynamics, pharmacokinetics, and metabolism of risperidone, use with concomitant medications, clinical trials in bipolar mania, as well as safety and tolerability issues. Finally, dosing and administration are addressed as well as use for bipolar mania in geriatric, child, or adolescent patients.