Ziprasidone in the management of schizophrenia : the QT interval issue in context

In vitro effects of antipsychotics on mitochondrial respiration

Assessment of drug-induced mitochondrial dysfunctions is important in drug development as well as in the understanding of molecular mechanism of therapeutic or adverse effects of drugs. The aim of this study was to investigate the effects of three typical antipsychotics (APs) and seven atypical APs on mitochondrial bioenergetics. The effects of selected APs on citrate synthase, electron transport chain complexes (ETC), and mitochondrial complex I- or complex II-linked respiratory rate were measured using mitochondria isolated from pig brain. Complex I activity was decreased by chlorpromazine, haloperidol, zotepine, aripiprazole, quetiapine, risperidone, and clozapine. Complex II + III was significantly inhibited by zotepine, aripiprazole, quetiapine, and risperidone. Complex IV was inhibited by zotepine, chlorpromazine, and levomepromazine. Mitochondrial respiratory rate was significantly inhibited by all tested APs, except for olanzapine. Typical APs did not exhibit greater efficacy in altering mitochondrial function compared to atypical APs except for complex I inhibition by chlorpromazine and haloperidol. A comparison of the effects of APs on individual respiratory complexes and on the overall mitochondrial respiration has shown that mitochondrial functions may not fully reflect the disruption of complexes of ETC, which indicates AP-induced modulation of other mitochondrial proteins. Due to the complicated processes associated with mitochondrial activity, it is necessary to measure not only the effect of the drug on individual mitochondrial enzymes but also the respiration rate of the mitochondria or a similar complex process. The experimental approach used in the study can be applied to mitochondrial toxicity testing of newly developed drugs.

An Inter-Ethnic Comparison Study of Ziprasidone Plasma Levels, Dosage and Clinical Response in Patients with Schizophrenia

OBJECTIVE

The aim of this study was to investigate ziprasidone plasma concentration, daily dose and clinical efficacy and safety in Han Chinese and Mongolian patients with first-episode schizophrenia.

METHODS

A total of 123 inpatients affected by schizophrenia were recruited from the Mental Health Center of Inner Mongolia in China. Ziprasidone plasma concentration, clinical efficacy and side effects were systematically evaluated at baseline, and at 1, 2, 4, and 6 weeks. Metabolic measures such as changes in weight, body mass index (BMI), fasting blood glucose (FBG), triglycerides, and cholesterol, were also recorded.

RESULTS

90 patients completed the study. Compared with Han patients, on average, Mongolian patients received a significantly higher ziprasidone dosage for adequate symptom control during the 6-week period and had a lower plasma concentration-to-dose ratio. The Mongolian patients also experienced greater increases in weight and BMI. No significant differences between the two ethnic groups were found in the rate of reduction in the Positive and Negative Syndrome Scale (PANSS) score, Treatment Emergent Symptom Scale (TESS) total score, FBG, triglycerides, cholesterol or Q-Tc interval.

CONCLUSION

Compared to Han Chinese patients, Mongolian patients appeared to have increased ziprasidone clearance and require higher doses to achieve effective treatment for schizophrenia.

Aggression in autism spectrum disorder: presentation and treatment options

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by persistent difficulties in social communication and social interaction, coupled with restricted, repetitive patterns of behavior or interest. Research indicates that aggression rates may be higher in individuals with ASD compared to those with other developmental disabilities. Aggression is associated with negative outcomes for children with ASD and their caregivers, including decreased quality of life, increased stress levels, and reduced availability of educational and social support. Therapeutic strategies including functional behavioral assessment, reinforcement strategies, and functional communication training may have a significant impact in reducing the frequency and intensity of aggressive behavior in individuals with ASD. Pharmacologic treatments, particularly the use of second-generation antipsychotics, may also be of some benefit in reducing aggression in individuals with ASD. With the ever-increasing rate of ASD diagnosis, development of effective therapeutic and pharmacologic methods for preventing and treating aggression are essential to improving outcomes in this disorder.

The improvement of the dissolution rate of ziprasidone free base from solid oral formulations

This work aims at increasing solubility and dissolution rate of ziprasidone free base-Biopharmaceutics Classifaction System (BCS) class II compound. The authors describe a practical approach to amorphization and highlight problems that may occur during the development of formulations containing amorphous ziprasidone, which was obtained by grinding in high-energy planetary ball mills or cryogenic mills. The release of ziprasidone free base from the developed formulations was compared to the reference drug product containing crystalline ziprasidone hydrochloride-Zeldox® hard gelatin capsules. All preparations were investigated using compendial tests (USP apparatuses II and IV) as well as novel, biorelevant dissolution tests. The novel test methods simulate additional elements of mechanical and hydrodynamic stresses, which have an impact on solid oral dosage forms, especially during gastric emptying. This step may prove to be particularly important for many formulations of BCS class II drugs that are often characterized by narrow absorption window, such as ziprasidone. The dissolution rate of the developed ziprasidone free base preparations was found to be comparable or even higher than in the case of the reference formulation containing ziprasidone hydrochloride, whose water solubility is about 400 times higher than its free base.

A Retrospective Naturalistic Study of Ziprasidone for Irritability in Youth with Autism Spectrum Disorder

OBJECTIVE

The purpose of this study was to assess the impact of ziprasidone monoantipsychotic treatment targeting irritability in a naturalistic outpatient autism spectrum disorder (ASD) clinical setting.

METHODS

We examined the use of ziprasidone, predominantly in combination with other psychotropic agents, targeting irritability in 42 youth with ASD in a large ASD-specific treatment database. Mean age at start of treatment, treatment duration, final dose, body mass index (BMI), BMI Z score, and Clinical Global Impressions-Improvement Scale (CGI-I) score at final visit were determined, and changes with treatment were analyzed using paired t tests. Cardiac corrected QT (QTc) interval data were extracted from electrocardiograms when available.

RESULTS

Mean age at start of treatment was 11.8 years. And final mean dose of ziprasidone was 98.7 mg/day or 1.7 mg/kg/day. Seventeen (40%) participants were considered treatment responders based on the CGI-I. No changes in QTc (although only examined in nine participants), weight, BMI, or other vital signs were noted, with ziprasidone use. The rate of treatment response was less than what has been reported for the two atypical antipsychotics, risperidone and aripiprazole, approved by the Food and Drug Administration (FDA) for the treatment of irritability in autistic disorder. The response rate with ziprasidone may be more consistent with response rates for other atypical antipsychotics, although none of these agents has been studied in larger-scale double-blind, placebo-controlled trials. The lower rate of response to ziprasidone in this open-label trial is likely influenced by the treatment-refractory nature of the population studied.

CONCLUSIONS

The weight neutrality of ziprasidone appears favorable compared with other second generation antipsychotics in this population. The response rate to ziprasidone targeting irritability may be lower than response rates associated with FDA-approved agents for this indication. Overall, ziprasidone use appeared well tolerated in youth with ASD.

Ventricular dysrhythmias associated with poisoning and drug overdose: a 10-year review of statewide poison control center data from California

BACKGROUND

Ventricular dysrhythmias are a serious consequence associated with drug overdose and chemical poisoning. The risk factors for the type of ventricular dysrhythmia and the outcomes by drug class are not well documented.

OBJECTIVE

The aim of this study was to determine the most common drugs and chemicals associated with ventricular dysrhythmias and their outcomes.

METHODS

We reviewed all human exposures reported to a statewide poison control system between 2002 and 2011 that had a documented ventricular dysrhythmia. Cases were differentiated into two groups by type of arrhythmia: (1) ventricular fibrillation and/or tachycardia (VT/VF); and (2) torsade de pointes (TdP).

RESULTS

Among the 300 potential cases identified, 148 cases met the inclusion criteria. Of these, 132 cases (89%) experienced an episode of VT or VF, while the remaining 16 cases (11%) had an episode of TdP. The most commonly involved therapeutic classes of drugs associated with VT/VF were antidepressants (33/132, 25%), stimulants (33/132, 25%), and diphenhydramine (16/132, 12.1%). Those associated with TdP were antidepressants (4/16, 25%), methadone (4/16, 25%), and antiarrhythmics (3/16, 18.75%). Drug exposures with the greatest risk of death in association with VT/VF were antidepressant exposure [odds ratio (OR) 1.71; 95% confidence interval (CI) 0.705-4.181] and antiarrhythmic exposure (OR 1.75; 95% CI 0.304-10.05), but neither association was statistically significant. Drug exposures with a statistically significant risk for TdP included methadone and antiarrhythmic drugs.

CONCLUSIONS

Antidepressants and stimulants were the most common drugs associated with ventricular dysrhythmias. Patients with suspected poisonings by medications with a high risk of ventricular dysrhythmia warrant prompt ECG monitoring.

QTc prolongation with antipsychotics: is routine ECG monitoring recommended?

Whether or not QTc interval should be routinely monitored in patients receiving antipsychotics is a controversial issue, given logistic and fiscal dilemmas. There is a link between antipsychotic medications and prolongation of QTc interval, which is associated with an increased risk of torsade de pointes (TdP). Our goal is to provide clinically practical guidelines for monitoring QTc intervals in patients being treated with antipsychotics. We provide an overview of the pathophysiology of the QT interval, its relationship to TdP, and a discussion of the QT prolonging effects of antipsychotics. A literature search for articles relevant to the QTc prolonging effects of antipsychotics and TdP was conducted utilizing the databases PubMed and Embase with various combinations of search words. The overall risk of TdP and sudden death associated with antipsychotics has been observed to be low. Medications, genetics, gender, cardiovascular status, pathological conditions, and electrolyte disturbances have been found to be related to prolongation of the QTc interval. We conclude that, while electrocardiogram (ECG) monitoring is useful when administering antipsychotic medications in the presence of co-existing risk factors, it is not mandatory to perform ECG monitoring as a prerequisite in the absence of cardiac risk factors. An ECG should be performed if the initial evaluation suggests increased cardiac risk or if the antipsychotic to be prescribed has been established to have an increased risk of TdP and sudden death.

Metoprolol and diltiazem ameliorate ziprasidone-induced prolonged corrected QT interval in rats

Ziprasidone, an atypical antipsychotic agent, has been shown to increase the corrected QT (QTc) interval in some patients. The aim of this study was to reveal the effects of metoprolol and diltiazem on ziprasidone drug-induced prolonged QTc interval. A total of 24 rats were equally divided into the following four groups: the first group was used as the control and received 1 mL/kg saline; 3 mg/kg ziprasidone and saline were administered to the second group; 3 mg/kg ziprasidone and 1 mg/kg metoprolol were administered to the third group and 3 mg/kg ziprasidone and 2 mg/kg diltiazem were administered to the fourth group. Two hours following application of the drugs, the QTc was calculated by performing electrocardiography in derivation (D)I. The duration of QTc interval was compared among the four groups. The mean QTc intervals were significantly increased in the third and fourth groups compared with the second group (p < 0.0005 and p < 0.0001, respectively). The study demonstrated the effectiveness of metoprolol and diltiazem in the prevention of ziprasidone-induced elongation in the QTc interval. Both metoprolol and diltiazem may be considered in the prophylactic therapy of high-risk patients who are using ziprasidone.

The psychopharmacology algorithm project at the Harvard South Shore Program: an update on schizophrenia

This article is an update of the algorithm for schizophrenia from the Psychopharmacology Algorithm Project at the Harvard South Shore Program. A literature review was conducted focusing on new data since the last published version (1999-2001). The first-line treatment recommendation for new-onset schizophrenia is with amisulpride, aripiprazole, risperidone, or ziprasidone for four to six weeks. In some settings the trial could be shorter, considering that evidence of clear improvement with antipsychotics usually occurs within the first two weeks. If the trial of the first antipsychotic cannot be completed due to intolerance, try another until one of the four is tolerated and given an adequate trial. There should be evidence of bioavailability. If the response to this adequate trial is unsatisfactory, try a second monotherapy. If the response to this second adequate trial is also unsatisfactory, and if at least one of the first two trials was with risperidone, olanzapine, or a first-generation (typical) antipsychotic, then clozapine is recommended for the third trial. If neither trial was with any these three options, a third trial prior to clozapine should occur, using one of those three. If the response to monotherapy with clozapine (with dose adjusted by using plasma levels) is unsatisfactory, consider adding risperidone, lamotrigine, or ECT. Beyond that point, there is little solid evidence to support further psychopharmacological treatment choices, though we do review possible options.

Single-dose ziprasidone associated with QT interval prolongation

Ziprasidone has been rarely associated with QT prolongation especially in patients (1) with no underlying cardiac or metabolic disorders, (2) who are receiving no concomitant medications known to prolong the QT interval, and (3) whom therapy is being initiated at a low dose. We report a 47-year-old patient who was agitated with suicidal ideation. He had a history of cocaine use, the last time being 72 hours before emergency department (ED) presentation. His electrocardiogram (ECG) on arrival in the ED showed a QT of 484 milliseconds and a QTc of 475 milliseconds with a pulse of 58 beats per minute. The patient was given 20 mg intramuscular (IM) ziprasidone for agitation. He reported feeling palpitations and weakness 45 minutes after receiving ziprasidone. His QT interval was prolonged on ECG and returned to baseline after 72 hours. Clinicians should consider obtaining an ECG before ziprasidone administration.

Maintenance therapies in bipolar disorders

OBJECTIVE

Bipolar disorder is an inherently recurrent disorder, requiring maintenance preventive treatments in the vast majority of patients. The authors review the data on maintenance treatments in bipolar disorder, highlighting the controlled trial literature.

METHODS

Literature review using PubMed, Medline, and a hand search of relevant literature.

RESULTS

Over the last decade, a number of effective maintenance treatments for bipolar disorder have been developed with an evidence base for second-generation antipsychotics and some anticonvulsants. Increasing numbers of patients, therefore, are appropriately treated with multiple medications as a maintenance regimen. For some medications, maintenance treatment has been demonstrated in randomized controlled trials for both monotherapy and in combination with other mood stabilizers. Lithium continues as our oldest well-established maintenance treatment in bipolar disorder with somewhat better efficacy in preventing mania than depression. Lamotrigine, olanzapine, and quetiapine have bimodal efficacy in preventing both mania and depression, although lamotrigine's efficacy is more robust in preventing depression and olanzapine's efficacy is greater in preventing mania. Aripiprazole, ziprasidone, and risperidone long-acting injection all prevent mania, but not depression. Less controlled investigations have suggested some evidence of maintenance mood stabilization with carbamazepine, oxcarbazepine, and adjunctive psychotherapy.

CONCLUSIONS

Despite the number of agents with demonstrated efficacy as maintenance treatments in bipolar disorder, optimal treatment regimens are still a combination of evidence-based therapy in combination with individualized creative treatment algorithms.

Sex difference in QTc prolongation in chronic institutionalized patients with schizophrenia on long-term treatment with typical and atypical antipsychotics

OBJECTIVE

The rate-corrected electrocardiographic QT (QTc) interval may significantly increase in patients with schizophrenia taking antipsychotics. The objective of this naturalistic study was to assess the prevalence of prolonged QTc interval in a large population of inpatients with chronic schizophrenia and to explore QTc relationship with demographic variables and prescribed treatments.

MATERIALS AND METHODS

Electrocardiograms were obtained from age- and sex-matched 456 controls and 1,006 inpatients with schizophrenia (male/female = 689/317) taking antipsychotics. QTc prolongation was defined as a mean value of two standard deviations above the controls. The adjusted relative risk was calculated using logistic regression analysis.

RESULTS

QTc prolongation was present in 45 (4.5%) of 1,006 patients overall. Fewer men (3.2%, 22 of 689) than women (7.3%, 23 of 317) displayed QTc prolongation (p < 0.004). Moreover, QTc intervals were shorter in male (391 ± 31 ms) than female subjects (400 ± 37 ms) (p < 0.001). Clozapine was found to produce a longer QTc intervals compared to risperidone and typical antipsychotics. Furthermore, multiple regression analysis showed that significant predictors for QTc prolongation were comorbid cardiovascular disease, antipsychotic types, sex, and age (all p < 0.01).

CONCLUSION

Our present findings suggest that there are sex differences in the prevalence of QTc prolongation and QTc lengthening in schizophrenia. Antipsychotic types are risk factors for QTc prolongation, and risks are substantially higher for clozapine.

Unmet treatment needs in schizophrenia patients: is asenapine a potential therapeutic option?

Adverse metabolic events, such as increased adiposity, hyperglycemia, diabetes mellitus and dyslipidemia, have been associated with treatment using atypical antipsychotic medications. However, the complexity of some of the reports on this problem and marketing efforts in this area may make it difficult for psychiatrists to remain fully and accurately informed about the metabolic complications of atypical antipsychotic therapy. Little is currently known about how psychiatrists view what they have read or heard, how they perceive the available information and how this affects their management of patients with schizophrenia. A number of studies have demonstrated that nonadherence to the medication regimen in schizophrenia is associated with poor symptomatic outcome, increased risk of relapse, more frequent use of compulsory treatment and increased risk of suicide and severe self-harm. Suicide is a major cause of death among schizophrenic patients, and their attitude toward medication can make the difference between a proper therapeutic regimen that protects patients from suicide risk versus discontinuation of treatments that are associated with disabling symptoms, some of which are risk factors for suicide. We review the characteristics of a new drug, asenapine, that may improve adherence in patients as a result of a distinctive receptor profile that may be associated with fewer side effects than other second-generation antipsychotic drugs.

Assessing QT interval prolongation and its associated risks with antipsychotics

Several antipsychotics are associated with the ventricular tachycardia torsade de pointes (TdP), which may lead to sudden cardiac death (SCD), because of their inhibition of the cardiac delayed potassium rectifier channel. This inhibition extends the repolarization process of the ventricles of the heart, illustrated as a prolongation of the QT interval on a surface ECG. SCD in individuals receiving antipsychotics has an incidence of approximately 15 cases per 10,000 years of drug exposure but the exact association with TdP remains unknown because the diagnosis of TdP is uncertain. Most patients manifesting antipsychotic-associated TdP and subsequently SCD have well established risk factors for SCD, i.e. older age, female gender, hypokalaemia and cardiovascular disease. QT interval prolongation is the most widely used surrogate marker for assessing the risk of TdP but it is considered somewhat imprecise, partly because QT interval changes are subject to measurement error. In particular, drug-induced T-wave changes (e.g. flattening of the T-wave) may complicate the measurement of the QT interval. Furthermore, the QT interval depends on the heart rate and a corrected QT (QTc) interval is often used to compensate for this. Several correction formulas have been suggested, with Bazett's formula the most widely used. However, Bazett's formula overcorrects at a heart rate above 80 beats per minute and, therefore, Fridericia's formula is considered more appropriate to use in these cases. Several other surrogate markers for TdP have been developed but none of them is clinically implemented yet and QT interval prolongation is still considered the most valid surrogate marker. Although automated QT interval determination may offer some assistance, QT interval determination is best performed by a cardiologist skilled in its measurement. A QT interval >500 ms markedly increases the risk for TdP and SCD, and should lead to discontinuation of the offending drug and, if present, correction of underlying electrolyte disturbances, particularly serum potassium and magnesium derangements. Before prescribing antipsychotics that may increase the QTc interval, the clinician should ask about family and personal history of SCD, presyncope, syncope and cardiac arrhythmias, and recommend cardiology consultation if history is positive.

Values of using QTc and N-terminal fragment of B-type natriuretic peptide as markers for early detection of acute antipsychotic drugs-induced cardiotoxicity

We aimed at studying the acute cardiotoxicity of the most commonly used antipsychotics in Egypt using QTc interval and NT-proBNP as markers for the early detection of such cases. Eighty-two admitted patients, at El-Minia PCC (period from 1-7-2005 to 30-6-2010), were classified into 3 groups: I: acute thioridazine overdose (n = 28), II: acute pimozide overdose (n = 23), and III: acute clozapine overdose (n = 31). Patients were investigated for NT-proBNP level and QTc on admission (day 0) and after 24 h (day 1). All the studied drugs had the ability to induce cardiotoxicity in the form of hypotension and dysrhythmias. Thioridazine and pimozide had potentially serious cardiotoxic effects than clozapine. NT-proBNP levels were elevated significantly in all groups on days 0 and 1 when compared with the reference value and a significant decrease in the same parameter on day 1 when compared with that of day 0 within the same group. QTc showed a significant prolongation in all studied groups on days 0 and 1, and there was a significant shortening of QTc on day 1 when compared with that of day 0 within the same group. A significant positive correlation of NT-proBNP level elevation with QTc prolongation was reported in all groups on days 0 and 1. Serious dysrhythmias were associated with QTc prolongation greater than 500 ms. And it was concluded that NT-proBNP, in adjunction with QTc measurement, may be a valuable and sensitive laboratory biomarker to predict cardiotoxicity of antipsychotic overdose. Larger multicenter studies are still needed to verify this possible relationship.

Drug safety evaluation of ziprasidone

INTRODUCTION

Ziprasidone is a second-generation antipsychotic approved for the treatment of schizophrenia and bipolar disorder. The purpose of this review is to assess the overall safety profile of ziprasidone, including its risk for prolonging the electrocardiogram (ECG) QT interval.

AREAS COVERED

This paper is a review of product labeling and English language reports located through PubMed and information available on regulatory agency websites, with a focus on the safety and tolerability of ziprasidone.

EXPERT OPINION

Although ziprasidone can prolong the ECG QT interval, this has not resulted in increases in sudden death or cardiac sudden death as noted in a large, simple trial and supported by almost a decade of real-world use in the US. Ziprasidone's principal advantage over some other second-generation antipsychotics has been its overall favorable weight and metabolic profile. Similar to most second-generation antipsychotics, ziprasidone has a lower propensity for extrapyramidal side effects and hyperprolactinemia compared to first-generation antipsychotics.

Ziprasidone hydrocloride: what role in the management of schizophrenia?

Background

Since schizophrenia is considered one of the top ten causes of disease-related disability in the world, the development of second-generation (atypical) antipsychotics (SGAs) has increased the hopes of psychiatrists. SGAs, however, cannot be considered a unique pharmacological class since each SGA has many complex pharmacologic actions, only some of which are shared with other SGAs. Even though manyantipsychotics have similar efficacy on average, prescribers may be able to achieve better than average results by considering differences in selecting a specific drug for a specific patient. Clinicians know that each patient is unique. In order to achieve best outcomes for the individual patient, the better therapy is the therapy tailored for the single patient.

Objectives

With this article, we provide information on a relatively new antipsychotic ziprasidone released in 2001 by Pfizer for the treatment of schizophrenia. Compared with other first line atypical antipsychotics ziprasidone has a unique profile due to potent interaction with serotonergic receptors and lesser action upon α1 adrenergic, H1 and M1 antagonist activities. This paper describes the development of ziprasidone, its unique properties and its metabolically-friendly profile including its receptor binding affinities, pharmacokinetics, CNS activity results of clinical efficacy and relevant clinical trials. Safety, efficacy and patient preference are also examined. The available literature on ziprasidone of the last five years is reviewed.

Safety of the electroconvulsive therapy-ziprasidone combination

In clinical practice, a nonnegligible proportion of patients with mood or psychotic disorders undergo electroconvulsive therapy (ECT) concomitantly with pharmacotherapy. Ziprasidone, a combined serotonin and dopamine receptor antagonist, is a second-generation antipsychotic agent with a lower incidence of extrapyramidal motor symptoms and prolactin elevation and a safer profile of adverse effects on plasma lipids, glucose levels, and body weight than other antipsychotics. To the best of our knowledge, there are as yet no available reports on the safety of the ECT-ziprasidone combination. We report here on a series of 8 female inpatients who underwent ECT while receiving ziprasidone (20-80 mg/d) as part of their regimen. Seven patients were treated for major depressive episode in the context of unipolar major depressive disorder (n = 5) or of bipolar disorder I (n = 2), whereas 1 patient was treated for exacerbation of schizophrenic symptoms. In all cases, the combination was well tolerated with only minimal adverse effects and unremarkable changes in corrected QT interval.

Management of schizophrenia with medical disorders: cardiovascular, pulmonary, and gastrointestinal

Medical illnesses are particularly common in patients who have schizophrenia and one of the major tasks for consultation-liaison psychiatrists, and others, is to determine which medications are safest in which co-morbid condition. The authors review the relative risks for various antipsychotics, especially focusing on cardiovascular, pulmonary, and gastrointestinal co-morbid illnesses. The authors further review the atypical antipsychotics' cardiovascular risks, especially for prolonging QT intervals, in trying to avoid the risk for torsades de pointes. The relative risk for anticholinergic actions for these medicines is also reviewed, as this is especially important in the medically ill or elderly. The authors also review the relative safety of antipsychotics in patients who have liver disease and pulmonary disease. Finally, the authors review specific drug interactions that may be problematic when treating the medically ill with atypical antipsychotics.

The potential relationship between QTc interval prolongation and ziprasidone treatment: three cases

QTc interval prolongation may appear as a consequence of both typical and atypical antipsychotic treatments. Ziprasidone, which is effective in treating schizophrenia, is associated with QTc prolongation. Although the prolongation of QTc with ziprasidone treatment is often pronounced, there is a scarce number of cases reported about the relationship between ziprasidone and QTc prolongation. Of the three cases presented in this case series, two cases showed values exceeding 0.50 s with ziprasidone treatment.

Using oral ziprasidone effectively: the food effect and dose-response

Ziprasidone is a newer "atypical" or "second-generation" antipsychotic. Oral ziprasidone (ziprasidone hydrochloride) has been approved by the US Food and Drug Administration (FDA) for the treatment of schizophrenia, and acute manic or mixed episodes associated with bipolar disorder (with or without psychotic features). Comparisons with other second-generation antipsychotics in meta-analyses reveal similar efficacy to that observed for quetiapine or aripiprazole, but inferior efficacy to that of olanzapine or risperidone in the treatment of schizophrenia. However, the rate of dose titration and the dose achieved may have an important bearing on ziprasidone's efficacy profile, with a target dose range of 120-160 mg/day being associated with optimal symptom control and greater persistence with treatment. In addition, enhancing ziprasidone's effectiveness requires ensuring that ziprasidone is administered with a 500 kcal meal; otherwise, absorption of oral ziprasidone is substantially reduced and cannot be compensated for by increasing the prescribed dose. Regarding tolerability, ziprasidone has important advantages in that it is not associated with clinically significant weight gain or adverse changes in cholesterol, triglycerides, or glycemic control, and patients may experience moderate improvement in these measures when switching to ziprasidone from a different antipsychotic. Ziprasidone also lacks significant persistent effects on prolactin levels, is not anticholinergic, and only infrequently causes extrapyramidal side effects or postural hypotension; however, it can be associated with somnolence. Ziprasidone may prolong the electrocardiogram (ECG) QT interval but this does not appear to pose a substantial clinical problem. Provided that an adequate dose of ziprasidone is prescribed, and administered with a 500 kcal meal, ziprasidone can be effectively used to control symptoms without the long-term liabilities of metabolic side effects.

Efficacy and tolerability of ziprasidone versus risperidone as augmentation in patients partially responsive to clozapine: a randomised controlled clinical trial

Patients suffering from schizophrenic psychoses sometimes insufficiently respond to antipsychotic monotherapy and then combination approaches are preferred. We aimed in validating the add-on of ziprasidone and risperidone to clozapine, and we performed a randomised head-to-head trial. Patients with partial response to clozapine were randomly attributed to augmentation with ziprasidone (n = 12) or risperidone (n = 12). Efficacy assessments included the Positive and Negative Syndrome Scale (PANSS), the Scale for the Assessment of Negative Symptoms (SANS), the Hamilton Depression Scale (HAMD), the Clinical Global Impression (CGI) and the Global Assessment of Functioning (GAF). Furthermore, several safety and tolerability measures were obtained. After six weeks, both groups showed significant reductions of positive and negative symptoms. In addition, affective state, psychosocial functioning and clozapine side effects improved without significant differences between the groups. Both approaches were well tolerated. However, the ziprasidone group experienced a small elongation of the QTc interval and a reduction of extrapyramidal symptoms. Patients under clozapine-risperidone therapy developed a rise of serum prolactin levels. The clozapine augmentation with ziprasidone or risperidone resulted in significant psychopathological improvements. The side effects differed between the treatment groups. Further head-to-head comparisons of atypical antipsychotics as add-on to clozapine are necessary.

In silico risk assessment for drug-induction of cardiac arrhythmia

The main components of repolarization reserve for the ventricular action potential (AP) are the rapid (I(Kr)) and slow (I(Ks)) delayed outward K(+) currents. While many drugs block I(Kr) and cause life-threatening arrhythmias including torsades de pointes, the frequency of arrhythmias varies between different I(Kr)-blockers. Different types of block of I(Kr) cause distinct phenotypes of prolongation of action potential duration (APD), increase in transmural dispersion of repolarization (TDR) and, accordingly, occurrence of torsades de pointes. Therefore the assessment of a drug's proarrhythmic risk requires a method that provides quantitative and comprehensive comparison of the effects of different forms of I(Kr)-blockade upon APDs and TDR. However, most currently available methods are not adapted to such an extensive comparison. Here, we introduce I(Kr)-I(Ks) two-dimensional maps of APD and TDR as a novel risk-assessment method. Taking the kinetics of I(Kr)-blockade into account, APDs can be calculated upon a ventricular AP model which systematically alters the magnitudes of I(Kr) and I(Ks). The calculated APDs are then plotted on a map where the x axis represents the conductance of I(Kr) while the y axis represents that of I(Ks). TDR is simulated with models corresponding to APs in epicardial, midcardial and endocardial myocardium. These two-dimensional maps of APD and TDR successfully account for differences in the risk resulting from three distinct types of I(Kr)-blockade which correspond to the effects of dofetilide, quinidine and vesnarinone. This method may be of use to assess the arrhythmogenic risk of various I(Kr)-blockers.

Iloperidone: a new benzisoxazole atypical antipsychotic drug. Is it novel enough to impact the crowded atypical antipsychotic market?

Iloperidone is a new-generation atypical antipsychotic agent, acting as a serotonin/dopamine (5-HT(2A)/D(2)) antagonist, under development by Vanda Pharmaceuticals for the treatment of schizophrenia, bipolar disorder and other psychiatric conditions. Chemically, iloperidone is a benzisoxazole, like risperidone, and shows a multiple receptor binding profile, sharing this feature with the other atypical antipsychotic agents. Administered orally, the drug is highly bound to plasma proteins and extensively metabolised. Several clinical trials have been carried out, to check efficacy, safety and side effects. In order to introduce iloperidone as an agent for the treatment of schizophrenia, a short overview of the disease and of the most important antipsychotic drugs available or under development will be reported. Iloperidone pharmacokinetics and pharmacodynamics are presented herein, together with an evaluation of clinical safety and efficacy results.

[Cardiological monitoring of antipsychotic-treated patients: evaluation and evolution of a hospital protocol]

INTRODUCTION

Following the Agence Française de Sécurité Sanitaire des Produits de Santé (Afssaps) (French Health Authority) recommendations in 2001, which impose the rigorous follow-up (electrocardiogram [ECG] and ionogram) of patients treated with antipsychotics (AP), a monitoring protocol was elaborated and set up in the Caen psychiatric hospital in April 2002. Protocol evaluation compared with fixed aims was performed after two years' follow-up.

AIM OF THE STUDY

This protocol had to answer a triple aim: better identification of patients at risk, ensure in-treatment monitoring, be simple and adapted to daily practice.

INCLUSION CRITERIA

A systematic admission check-up (S0) which includes cardiological and biological controls and after one and six months' treatment control (S1 and S6) were recommended. The major risk factors (RF) researched were long QT interval, bradycardia and hypokaliemia.

RESULTS

The initial monitoring was conducted in 601 patients (that only corresponded to 17% of hospital admission active files during the considered period). Means delays before obtaining an ECG were three times those obtained existing biological check-ups (11 days versus three days after date of admission). Systematic and integrated characterisation controls on admission were not respected. We noted that two-third of patients admitted during this period were hospitalized for only five days, although the mean time to obtain an ECG is of 11 days. This delay (approximately one week) between ECG and biological check-up is not compatible with a complete patient RF evaluation. Respectively, 83 and 68 patients were controlled under treatment at S1 and S6. Only half of the patients were controlled at the one-month (S1) and 16% at the six-months' theoretical dates (S6). These delays are inappropriate, notably with regard to the mean time of hospitalisation (15-17 days). The incidence of major RF was higher in treated (71%) than in non-treated patients. Major RF presence at S0 was not systematically associated with an AP treatment contraindication. The excessive delay before the first ECG could partially explain why this initial check-up was not able to detect a pretreatment contraindication. On the other hand, AP treated patients who presented at least one major RF at S0 were more frequently monitored at S1 than patients who did not (26% versus 13%, p=0.05). Among the 168 patients treated with AP or other drugs prolonging the QT interval at risk, 33 had at least one follow-up. This risk population was not better controlled than the initial cohort.

DISCUSSION

Protocol evaluation is essential to improve its interest and feasibility. If systematic characterisation is simple, its application in practice is very difficult. The second version of the protocol presented here proposes to substitute the systematic ECG characterisation with the classification on admission of patients in "risk groups" that will condition the subsequent monitoring. Risk groups are identified into two RF types: those which are not related to AP treatment and those which are therapeutic attitude is adapted according to initial QTcorrigé (QTc), its progression between S0 and S (seven days) and kaliemia.

Ziprasidone for schizophrenia and bipolar disorder: a review of the clinical trials

Ziprasidone is a newer "atypical" or "second-generation" antipsychotic. Oral ziprasidone (ziprasidone hydrochloride) is approved by the U.S. Food and Drug Administration (FDA) for the treatment of schizophrenia, and acute manic or mixed episodes associated with bipolar disorder (with or without psychotic features). Ziprasidone intramuscular (ziprasidone mesylate) is FDA-approved for acute agitation in patients with schizophrenia. Oral ziprasidone appears efficacious, and has been shown to have some limited clinical advantages over chlorpromazine and haloperidol in ameliorating negative symptoms of schizophrenia. In Phase 2 of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) for schizophrenia, ziprasidone did not match the clinical performance of olanzapine and risperidone, appearing closer in overall effectiveness to quetiapine. The rate of dose titration and the dose achieved may have an important bearing on ziprasidone's efficacy profile. In studies of usage for acute agitation in individuals with schizophrenia, intramuscular ziprasidone has been shown to be efficacious and relatively well tolerated. Regarding tolerability, ziprasidone, has important advantages in that it is not associated with clinically significant weight gain or adverse changes in cholesterol, triglycerides, or glycemic control, and patients may experience moderate improvement in these measures when switching to ziprasidone from a different antipsychotic agent. It also lacks significant persistent effects on prolactin levels, is not anticholinergic, and only infrequently causes extrapyramidal side effects or postural hypotension, although it can be associated with somnolence. This tolerability profile may be quite valuable in the treatment of some patients. Ziprasidone may prolong the electrocardiogram (ECG) QTc interval (QT interval corrected for heart rate by a standard algorithm), but after 5 years' clinical availability ziprasidone (by itself) does not appear to pose a substantial clinical problem in this regard. Therefore, ziprasidone may be considered a first-line drug option in the treatment of schizophrenia or manic episodes, but, in view of the differences among antipsychotic medications, drug selection should be guided by the patient's individual characteristics and situation.

The use of intramuscular benzodiazepines and antipsychotic agents in the treatment of acute agitation or violence in the emergency department

The management of an agitated, abusive or violent patient is a common and challenging problem in Emergency Medicine. Priorities include measures to ensure the safety of the patient and the emergency staff, including provision of physical restraint of the patient and evaluation for correctable medical causes of such behavior. Medications used in the treatment of such patients include benzodiazepines and antipsychotic agents. The newer atypical antipsychotic agents seem to provide a safe and effective treatment for such patients. The atypical antipsychotic agents may have fewer short-term side effects than older typical antipsychotic agents, such as haloperidol and droperidol. Currently available atypical antipsychotic medications for the treatment of acute agitation include ziprasidone and olanzapine, which can be administered in an intramuscular formulation, and risperidone, which is available in a rapidly dissolvable tablet and liquid formulation.

Probable Association Between Ziprasidone and Worsening Hypertension

According to premarketing studies, at least 1% of ziprasidone-treated patients exhibited hypertension; however, this figure is not necessarily attributable to the drug. A PubMed/MEDLINE search yielded no articles describing hypertension as a possible adverse event associated with oral ziprasidone therapy. We describe a 53-year-old African-American woman with hypertension and schizophrenia whose blood pressure increased during ziprasidone therapy. She experienced no similar blood pressure increases during therapy with four other atypical antipsychotics. Her mean systolic blood pressure during ziprasidone treatment (158 mm Hg) was significantly higher than before (141 mm Hg) and after (135 mm Hg) treatment. Also, her mean diastolic blood pressure during ziprasidone treatment (88 mm Hg) was significantly higher than after treatment (79 mm Hg). Linear regression analysis demonstrated that the patient's systolic blood pressure increased significantly with ziprasidone dose (regression coefficient [B] = 0.22 mm Hg x day/mg, 95% confidence interval 0.10-0.34, p=0.001). Thus, after adjusting for the effect of antihypertensive doses, an increase of 40 mg/day in ziprasidone yielded an increase of 8.8 mm Hg in systolic blood pressure. For unknown (perhaps genetic) reasons, this patient may have been particularly sensitive to ziprasidone. Clinicians prescribing ziprasidone in patients with hypertension should be aware that their hypertension could worsen with the addition of ziprasidone. If this occurs, replacement of ziprasidone with a different antipsychotic should be considered.

Amisulpride in the treatment of behavioural disturbances among patients with moderate to severe Alzheimer's disease

OBJECTIVE

The aim of this article was to evaluate the effects of amisulpride on the behavioural and psychiatric symptoms of patients with Alzheimer's disease (AD).

MATERIALS AND METHODS

In this open-label study, we observed 18 outpatients affected by moderate to severe AD, complicated with agitation and disruptive behaviours. Behavioural, cognitive and motor effects of amisulpride at baseline and after 12 weeks were rated by the Neuropsychiatric Inventory (NPI), Mini Mental State Examination, Clinical Dementia Rating Scale, activities of daily living, and the motor score of the Unified Parkinson's Disease Rating Scale.

RESULTS

After treatment with amisulpride (200 mg/day), the patients showed a significant decrease in NPI total scores, particularly for the subitem 'agitation'. Cognitive and motor variables did not worsen significantly over the 12-week period.

CONCLUSIONS

This preliminary observation suggests that amisulpride can be useful to control agitation and disruptive behaviours in AD patients without significantly effecting vigilance and motor activity.

Pharmacotherapy of delusional disorders in the context of offending and the potential for compulsory treatment

Delusional disorder is an uncommon mental illness with an estimated prevalence of 0.03%. Its low prevalence has likely contributed to the paucity of research interest in this area, leading to substantial gaps in knowledge concerning its treatment and management. In the absence of a robust literature, most clinicians rely on their experience and guidelines for treating schizophrenia when treating patients with delusional disorder. This article reviews the available literature that is specific to the treatment of delusional disorder. In addition, it focuses on specific forensic and medicolegal aspects of managing patients with delusional disorder.

Ziprasidone: a review of its use in schizophrenia and schizoaffective disorder

Ziprasidone (Geodon, Zeldox) is an atypical antipsychotic agent with a unique neurotransmitter receptor-binding profile. The oral formulation is indicated for the treatment of adult patients with schizophrenia and the intramuscular formulation for the control of acute agitation in these patients. In adult patients with schizophrenia or schizoaffective disorder, oral ziprasidone was effective at a dosage of 40-80 mg twice daily in patients experiencing a phase of acute illness, and at a dosage of 20-80 mg twice daily in those with chronic schizophrenia or schizoaffective disorder, including those who were symptomatically stable. Ziprasidone offers the advantage over most other atypical antipsychotic agents of being available in a fast-acting intramuscular formulation for control of acute agitation, thus providing clinicians with the option to safely and effectively transition to longer-term treatment with the oral formulation. Although careful consideration should be given to the propensity for ziprasidone to cause corrected QT (QTc) interval prolongation, albeit at a relatively low incidence, the drug generally has a favourable tolerability profile of low extrapyramidal syndrome (EPS) liability, neutral bodyweight gain, and potentially low propensity for metabolic complications. Thus, ziprasidone is an effective option for the management of patients with schizophrenia or schizoaffective disorder, with the intramuscular formulation providing a useful option for the treatment of acute agitation in these patients.

Block of hERG channel by ziprasidone: biophysical properties and molecular determinants

Ziprasidone, an antipsychotic agent, delays cardiac repolarization and, thus, prolongs the QT interval of the cardiac ECG. In this study, we examined the biophysical properties and the molecular determinants of the ziprasidone block of wild-type hERG potassium channels stably expressed in HEK-293 cells or wild-type and mutant hERG channels expressed in Xenopus oocytes. In stably transfected HEK-293 cells, ziprasidone blocked wild-type hERG current in a voltage- and concentration-dependent manner (IC(50)=120nM, 0mV, 37 degrees C). Ziprasidone showed minimal tonic block of hERG current estimated during a depolarizing voltage (-20 or +30mV) or evaluated by the envelope of tails test (+30mV). Rate of the block onset was rapid, but not significantly affected by test potentials ranging from -20 to +30mV (time constant (tau)=114+/-14ms at +30mV). The time constant of the slow component of hERG current deactivation (at -50mV) was significantly increased by ziprasidone (tau=1776+/-90 versus 1008+/-71ms, P<0.01). Time course of channel inactivation was slowed by ziprasidone in a voltage-dependent manner. The V(1/2) values for steady-state activation and inactivation of hERG channel in HEK-293 cells were not significantly altered by ziprasidone. In Xenopus oocytes, ziprasidone exhibited less potent block of wild-type hERG current (IC(50)=2.8microM, 0mV, 23 degrees C). Mutation of the aromatic residues (Tyr-652 or Phe-656) located in the S6 domain of hERG dramatically reduced the potency of channel block by ziprasidone (IC(50)>0.4 and 1mM at 0mV for Y652A and F656A, respectively). In conclusion, ziprasidone preferentially binds to and blocks open hERG channels. Tyr-652 and Phe-656 are two critical residues in the ziprasidone-binding site.

Are hERG channel inhibition and QT interval prolongation all there is in drug-induced torsadogenesis? A review of emerging trends

Contemporary preclinical in vitro and in vivo methods have been imperfect in predicting drug-induced Torsades de Pointes (TdP) in humans. A better understanding of additional relevant factors in the genesis of drug-induced TdP is necessary. New sophisticated in vitro techniques, such as arterially perfused ventricular wedge preparations or isolated perfused hearts, potentially offer a better understanding of torsadogenic mechanisms and a refinement of drug testing. Of particular interest are the dispersion of repolarization and the refractoriness of different cell types across the ventricular wall, triangulation of the action potential, reverse use dependence and instability of the action potential duration. In vivo models are currently refined by establishing parameters such as beat-to-beat variability and T-wave morphology as derived from the in vitro proarrhythmia indices. Animal models of proarrhythmia are to date not recommended for routine evaluation. A pharmacodynamic interaction with combinations of torsadogenic compounds is another area to be considered. Little is known about channel/receptor cross talk, although considerable evidence exists that cardiac G protein-coupled receptors can modulate hERG channel function. More investigations are necessary to further evaluate the role of altered gene expression, mutations, and polymorphisms in drug-induced TdP. A novel mechanism of drug-induced torsadogenesis is the reduced expression of hERG channel protein on the plasma membrane due to a trafficking defect. Pharmacokinetic and metabolism data are crucial for calculating the risk of a torsadogenic potential in man. Consideration of intracardiac accumulation can help in delineating pharmacokinetic-pharmacodyamic relationships. In silico virtual screening procedures with new chemical entities to predict hERG block may develop as a promising tool. The role of in silico modeling of TdP arrhythmia is likely to become increasingly important for organizing and integrating the vast amount of generated data. At present, however, in silico methods cannot replace existing preclinical in vitro and in vivo models.

Guide to anaesthetic selection for electroconvulsive therapy

Electroconvulsive therapy (ECT) is used in the treatment of severe psychiatric disorders. It involves the induction of a seizure for therapeutic purposes by the administration of a variable-frequency electrical stimulus via electrodes applied to the scalp. The original application of ECT in non-anaesthetised patients resulted in many traumatic effects and was replaced, in the early 1960s, with a modified ECT regimen that used anaesthesia with neuromuscular blockade. This remains the worldwide standard today. The development of modern ECT devices, with improved impulse modes, has also reduced the incidence of post-interventional cognitive adverse effects. The variety of centrally-acting co-medications administered and the cardiovascular effects occurring during the procedure make patients receiving ECT a challenge for the anaesthetist. The efficacy of ECT depends on the production of adequate seizures; however, the anaesthetic agents commonly used during ECT suppress the generation of convulsions. Therefore, the efficacy of ECT requires knowledge of anaesthetic precepts, understanding of the interaction between anaesthetic drugs and seizure activity, and awareness of the physiological effects of ECT as well as the treatment of those effects. Successful and safe ECT depends on the correct choice of anaesthetic drugs for the individual patient, which have to be chosen with respect to the individual concomitant medication and pre-existing diseases. This review provides information for the optimal selection, set-up and practice of anaesthetic drug treatment in ECT.

From clinical research to clinical practice: a 4-year review of ziprasidone

Ziprasidone is a second-generation antipsychotic that received Food and Drug Administration approval in February 2001. It has a unique receptor profile that includes high-affinity antagonist activity at dopamine D2 receptors, inverse agonist activity at serotonin (5-HT)2A receptors, agonist activity at 5-HTlA receptors, and a relatively high affinity for the serotonin and norepinephrine transporters. The 5-HTIA affinity, together with the inhibitory effect on mono-amine reuptake, may underlie the hypothesized beneficial effects on comorbid affective and cognitive abnormalities in schizophrenia and schizoaffective disorder. The short-term efficacy of ziprasidone for core positive symptoms of schizophrenia appears to be comparable to other conventional and atypical antipsychotics. The short-term efficacy of ziprasidone in acute mania has been established based on two 3-week, double-blind, placebo-controlled trials.Open-label treatment for up to 52 weeks confirms the sustained efficacy and safety of ziprasidone in bipolar disorder. Maintenance studies in schizophrenia and schizoaffective disorder indicate that long-term ziprasidone therapy is effective in preventing relapse, while maintaining cognitive and psychosocial benefits. The safety database suggests that the overall cardiovascular and cerebrovascular risk associated with ziprasidone is lower than with other atypicals, with notably lower risk of drug-related increases in weight, glucose, or lipids. The data also suggest a modestly increased risk of QTc prolongation that is not dose related or linked to torsades de pointes. Switching to ziprasidone from other atypicals appears to improve both clinical symptoms and metabolic parameters, though more studies are needed to fully characterize these benefits. This monograph summarizes the efficacy, tolerability, and safety of oral ziprasidone in the treatment of schizophrenia, schizoaffective disorder, and bipolar mania.

Additive effects of ziprasidone and d,l-sotalol on the action potential in rabbit Purkinje fibres and on the hERG potassium current

INTRODUCTION

Ziprasidone, an atypical antipsychotic has been shown to be devoid of cardiac adverse effects in spite of its propensity to prolong the QT-interval via a hERG current inhibition. However, the effects of ziprasidone on the action potential (AP) parameters have not been published yet. Moreover, very little information is available concerning pharmacodynamic interactions between ziprasidone and other hERG channel blockers. Thus, we investigated the putative interaction between ziprasidone and D,L-sotalol on the hERG channels at therapeutic concentrations and their consequences on the action potential prolongation.

METHODS

AP were recorded at 1 and 0.2 Hz. Increasing concentrations of ziprasidone (0.01-10 micromol/L) were successively superfused for 30 min alone or in D,L-sotalol 10 micromol/L pre-treated fibres. Moreover, the effects of ziprasidone, alone or in association with d,l-sotalol, were investigated on the hERG current.

RESULTS

Ziprasidone (1-10 microM) induced a concentration and reverse frequency-dependent increase in APD(90) (APD(90): +27% and +36%, respectively at 1 Hz and +50% and +70%, respectively at 0.2 Hz) due to a hERG current blockade (IC50: 0.24 micromol/L). A pre-treatment with D,L-sotalol 10 micromol/L led to an increase in APD(90) of +23% at 1 Hz, stable at 66+/-4 min. In these pre-treated fibres, ziprasidone (1 and 10 micromol/L) induced an additional AP prolongation (APD(90): +16% and +18%, respectively at 1 Hz) as compared to D,L-sotalol pre-treatment. Moreover, D,L-sotalol did not interact with the pharmacological profile of ziprasidone on the hERG channel.

CONCLUSION

The present study demonstrates that ziprasidone induces an AP prolongation due to its propensity to block the hERG channel. Moreover, ziprasidone and d,l-sotalol, superfused concomitantly exhibit additive effects on the AP duration since they do not interact as competitors for the hERG channel.

Treatment of behavioural and psychiatric symptoms in dementia: implications of recent safety warnings

Atypical antipsychotics are commonly used off-label to treat behavioural and psychiatric symptoms in dementia (BPSD), particularly in elderly care homes. Much of this use is inappropriate, and trials have shown an increased likelihood of serious cerebrovascular adverse events (CVAEs) such as stroke and transient ischemic attack (TIA) in elderly patients. The aetiology of this risk is not known, but may be related to metabolic effects and excess weight gain. Based on a review of published trials with risperidone and olanzapine that shows a three-fold increase in stroke risk in elderly patients with dementia, regulators in Europe and the USA now recommend against using these agents for behavioural control, particularly in patients with a history of cerebrovascular disease. When making prescribing decisions, physicians should pay careful attention to risk versus benefit with psychotropics. Antipsychotics should be regarded only as rescue medications for acute-onset (over hours or days) or for severe chronic BPSD, or used in patients who are aggressive and/or represent a danger to themselves or others. If atypical antipsychotics are prescribed, physicians should screen for risk factors for both stroke and cardiovascular disease when initiating treatment, and regular monitoring should be undertaken if patients with chronic behavioural problems receive antipsychotic maintenance therapy. International guidelines are now required that direct prescribers in the appropriate use of alternative therapies for BPSD. Cholinesterase inhibitors (ChEIs), particularly rivastigmine, can delay the onset and reduce the severity of neuropsychiatric symptoms in dementia, and decrease the requirement for antipsychotic and other psychotropic medications. Evidence suggests that they may be more appropriate for the control of chronic (over weeks to months) mild-to-moderate BPSD.

Atypical antipsychotics and metabolic dysregulation: evaluating the risk/benefit equation and improving the standard of care

Atypical antipsychotics are a major advance in the management of schizophrenia. The reevaluation of widely held risk/benefit assessments of the various atypical antipsychotics provides an opportunity to improve treatment patterns. The best available clinical trial evidence indicates that efficacy among the atypical antipsychotics (at equivalent doses) is very similar, but safety and tolerability profiles differ significantly. Atypical antipsychotics differ markedly in their potential to cause metabolic disturbances, including obesity, diabetes, dyslipidemia, and the metabolic syndrome; clozapine and olanzapine carry the greatest risks, atypical antipsychotics like risperidone and quetiapine have lower risks, and newer agents like ziprasidone and aripiprazole are associated with minimal metabolic risks. Results from the Atypical Antipsychotic Therapy and Metabolic Issues (AtAMI) survey define important opportunities for improving medical and psychiatric outcomes during atypical antipsychotic therapy. (See accompanying article by Newcomer et al) Additional educational and research efforts are required to increase understanding of common conditions such as the metabolic syndrome, increase awareness of uncommon but serious events like diabetic ketoacidosis, and pancreatitis, and identify appropriate strategies for monitoring the risks/benefits of atypical antipsychotic therapy. As clinicians refine practice patterns regarding the atypical antipsychotics, they may require additional knowledge and resources to fully incorporate risk/benefit considerations and optimize long-term psychiatric and medical outcomes.

Dose response and atypical antipsychotics in schizophrenia

Based on information from clinical trials, both the efficacy and adverse effects of conventional antipsychotics in the treatment of schizophrenia are dose related. The overlapping nature of these dose-response profiles limits the use of these agents. Atypical antipsychotics provide greater relief across the comorbid symptom domains of schizophrenia, but dose-response studies and clinical experience have revealed that some of these drugs also have dose limitations. This article reviews the dose-response relationships of the atypical antipsychotics as presented predominantly in pivotal, randomised studies (double-blind and otherwise). Limited data indicate that clozapine shows dose-related efficacy up to 600 mg/day in patients with treatment-resistant schizophrenia. However, higher dosages of clozapine may be associated with the risk of seizures. Risperidone demonstrates dose-related adverse events that compromise efficacy. The dose-response relationships for ziprasidone, quetiapine and aripiprazole are less well established. The efficacy of olanzapine appears to be dose related within the recommended dosage range of 10-20 mg/day, but clinical trials that have explored higher dosages suggest improved efficacy. Furthermore, the higher doses are not associated with a significantly increased incidence of adverse events. Further studies are clearly needed to fully characterise the dose-response relationships of atypical antipsychotics.