First-episode schizophrenia: a focus on pharmacological treatment and safety considerations

Schizophrenia is a debilitating disorder, which is usually chronic, and is one of the most devastating medical illnesses. Early and appropriate treatment with antipsychotics is an important strategy for patients with first-episode schizophrenia. However, there are many possible safety issues for patients with schizophrenia that should be considered and properly addressed. Depressive symptoms and suicidal behaviour commonly occur in first-episode schizophrenic patients, and every effort should be made to treat and minimise these symptoms. There are also important issues and considerations in young and first-episode patients that should also be considered in the emergency treatment setting and for minimising medication nonadherence in this population. Most importantly, adverse effects should be considered, minimised and addressed. While first- and second-generation antipsychotics (SGAs) both appear to offer similar efficacy for amelioration of positive symptoms in first-episode patients, SGAs may offer better tolerability, specifically regarding extrapyramidal symptoms (EPS) and tardive dyskinesia risk, and some prolactin-sparing benefits. However, these medications do cause a host of adverse effects, including weight gain, metabolic disturbances, corrected QT interval prolongation and prolactin-related adverse effects, which are important considerations relating to both the short- and long-term safety of patients with schizophrenia being treated with SGAs. Clozapine and olanzapine are most likely to cause weight gain and metabolic effects, while risperidone is more likely to cause EPS and prolactin elevations. Most antipsychotics should be used in low doses to minimise adverse effects and each medication should be optimised in a highly individualised way to maximise adherence and treatment outcomes and minimise tolerability and safety concerns. At some point in their lives, these patients will most probably experience periods of depression, suicidal behaviours, adverse effects and nonadherence, and every effort should be made to minimise or prevent these from occurring. Thus, safety concerns in this group of young patients, in the beginning of their first psychotic episode, are a major issue as they are starting a journey of antipsychotic treatment that is likely to last for the remainder of their lives.     

The effect of reboxetine co-administration with olanzapine on metabolic and endocrine profile in schizophrenia patients

Rationale

We previously demonstrated that the addition of the selective norepinephrine reuptake inhibitor reboxetine attenuates olanzapine-induced weight gain. Using the same study sample, we also sought to determine whether reboxetine’s weight-attenuating effect was accompanied by a beneficial effect on metabolic and endocrine parameters relevant to antipsychotic-induced weight gain and obesity.

Method

Blood samples at baseline and at the end of the 6-week trial were available for 54 participants who participated in previous double-blind, placebo-controlled studies of reboxetine (4 mg BID) addition to olanzapine-treated schizophrenia patients. Fasting glucose, lipid profile, insulin, leptin, cortisol, dehydroepiandrosterone (DHEA), prolactin, and thyroid-stimulating hormone (TSH) were analyzed.

Results

In contrast to the olanzapine/placebo group, the olanzapine/reboxetine group exhibited a reduction in blood triglyceride (p?<?0.05) and leptin (p?<?0.05) levels, and elevation in cortisol (p?<?0.05) and DHEA (p?<?0.008) levels. No significant between-group differences were detected in the changes in cholesterol, glucose, insulin, TSH, and prolactin.

Conclusions

Reboxetine addition resulted in meaningful improvement of some metabolic and endocrine measures associated with olanzapine-induced weight gain. The potential role of reboxetine in the prevention of olanzapine-induced weight gain and cardio–metabolic morbidity merits further large-scale, long-term investigation.     

The safety and tolerability of atypical antipsychotics in bipolar disorder

Atypical antipsychotics (aAPs), have become a first-line treatment option, both in schizophrenia and bipolar disorders. Almost all aAPs now have proven efficacy in acute mania, some also in bipolar depression and in maintenance treatment. This provides reliable data on their safety and tolerability in this particular group of patients. This review focuses on the safety and tolerability of aAPs in the treatment of bipolar disorders. Both tolerability, for example, extrapyramidal symptoms, and safety issues, for example, occurrence of weight gain and hyperglycaemia, will be highlighted for olanzapine, quetiapine, risperidone, ziprasidone and aripiprazole.     

Intramuscular aripiprazole : a review of its use in the management of agitation in schizophrenia and bipolar I disorder

An intramuscular formulation of the atypical antipsychotic aripiprazole (Abilify) has been developed and is approved in the EU for use in agitation and disturbed behaviour associated with schizophrenia. In the US, it is approved for the treatment of agitation associated with schizophrenia or bipolar I disorder (manic or mixed). In large, well designed trials, intramuscular aripiprazole was an effective and generally well tolerated treatment for agitation associated with schizophrenia, schizoaffective disorder, schizophreniform disorder or bipolar I disorder. Intramuscular aripiprazole was more effective than placebo in these patient populations and was noninferior to intramuscular haloperidol in those with agitation associated with schizophrenia and its related disorders. Aripiprazole is associated with a low risk for extrapyramidal symptoms (EPS), cardiac effects, hyperprolactinaemia, weight gain and other metabolic disturbances. Head-to-head trials comparing intramuscular aripiprazole with other intramuscular atypical antipsychotics are required before the relative position of each of these agents can be fully determined. In the meantime, intramuscular aripiprazole, with its favourable tolerability profile, is a valuable treatment option for agitation in patients with schizophrenia, schizoaffective disorder, schizophreniform disorder or bipolar I disorder.     

Insulin and glucose metabolism with olanzapine and a combination of olanzapine and samidorphan: exploratory phase 1 results in healthy volunteers

A combination of olanzapine and samidorphan (OLZ/SAM) received US Food and Drug Administration approval in May 2021 for the treatment of adults with schizophrenia or bipolar I disorder. OLZ/SAM provides the efficacy of olanzapine, while mitigating olanzapine-associated weight gain. This exploratory study characterized the metabolic profile of OLZ/SAM in healthy volunteers to gain mechanistic insights. Volunteers received once-daily oral 10 mg/10 mg OLZ/SAM, 10 mg olanzapine, or placebo for 21 days. Assessments included insulin sensitivity during an oral glucose tolerance test (OGTT), hyperinsulinemic-euglycemic clamp, other measures of glucose/lipid metabolism, and adverse event (AE) monitoring. Treatment effects were estimated with analysis of covariance. In total, 60 subjects were randomized (double-blind; placebo, n = 12; olanzapine, n = 24; OLZ/SAM, n = 24). Olanzapine resulted in hyperinsulinemia and reduced insulin sensitivity during an OGTT at day 19, changes not observed with OLZ/SAM or placebo. Insulin sensitivity, measured by hyperinsulinemic-euglycemic clamp, was decreased in all treatment groups relative to baseline, but this effect was greatest with olanzapine and OLZ/SAM. Although postprandial (OGTT) glucose and fasting cholesterol concentrations were similarly increased with olanzapine or OLZ/SAM, other early metabolic effects were distinct, including post-OGTT C-peptide concentrations and aspects of energy metabolism. Forty-nine subjects (81.7%) experienced at least 1 AE, most mild or moderate in severity. OLZ/SAM appeared to mitigate some of olanzapine’s unfavorable postprandial metabolic effects (e.g., hyperinsulinemia, elevated C-peptide) in this exploratory study. These findings supplement the body of evidence from completed or ongoing OLZ/SAM clinical trials supporting its role in the treatment of schizophrenia and bipolar I disorder.Subject terms: Medical research, Developmental biology     

A parametric analysis of olanzapine-induced weight gain in female rats

RATIONALE: Some novel antipsychotics, including olanzapine, induce weight gain and metabolic abnormalities, which represent the major adverse effects of these drugs. However, the mechanism(s) involved in such effects are unclear. OBJECTIVE: The aim of this study was to develop, in female rats, a parametric model of olanzapine-induced weight gain and metabolic abnormalities and evaluate it against clinical findings. METHODS: Female rats were administered olanzapine b.i.d. at doses of 0, 1, 2 and 4 mg/kg over 20 days, and a wide range of variables were recorded during and after drug administration. RESULTS: Olanzapine increased both 24 h and total food intake. This was associated with rapid onset weight gain and increased adiposity (assessed by visceral fat pad masses). Insulin, but not glucose, concentrations were elevated, with a significant increase in the HOMA-IR index, indicative of insulin resistance. A nonsignificant trend towards higher levels of leptin was observed. Paradoxically, there was a significant increase in adiponectin. All of these variables showed maximal increases at either 1 or 2 mg/kg and attenuated effects at 4 mg/kg. Prolactin levels were also increased by olanzapine. However, for this variable, there was a clear dose-response curve, with the maximal effect at the highest dose (4 mg/kg). CONCLUSIONS: These data suggest that aspects of olanzapine-induced weight gain and metabolic abnormalities can possibly be modelled in female rats. It is suggested that olanzapine-induced hyperphagia acts as an initial stimulus which leads to weight gain, enhanced visceral adiposity and subsequent insulin resistance, although the latter may be ameliorated by compensatory responses in adiponectin levels. Prolactin elevation appears likely not to be involved in the weight gain, adiposity and metabolic changes seen in this model.     

Perceptions of weight gain and bipolar pharmacotherapy: results of a 2005 survey of physicians in clinical practice

ABSTRACT

Objective: To assess the perceptions of clinicians in the psychiatric community about pharmacotherapy and its impact on weight gain and adverse metabolic effects in patients with bipolar disorder.

Methods: In November 2005, self-administered questionnaires were sent to 7000 psychiatrists who treat bipolar disorder in their clinical practice. An additional mailing of these questionnaires was sent in January 2006 to a different group of 7000 psychiatrists who treat bipolar disorder in their clinical practice. The first 298 completed surveys were analyzed.

Results: Almost half of the respondents (48%) were psychiatrists in individual private practice and 32% were in community mental health centers. About two-thirds of respondents reported that 30–60% of their bipolar patients were overweight. Thirty-eight percent of respondents reported metabolic syndrome present in 20–40% of their patients. Almost all respondents (96%) reported a 20?lb increase in patients’ weight as a troublesome potential adverse event associated with the use of some agents. After initiating a new medication, more than 80% of respondents monitored their patients’ weight, fasting plasma glucose level, and fasting lipid profile at regular intervals. However, 80% did not monitor waist circumference. Overall, respondents viewed several agents (aripiprazole, ziprasidone, carbamazepine, and lamotrigine) as not (or minimally) problematic in terms of weight gain and adverse metabolic concerns. Clozapine and olanzapine were viewed as highly problematic due to their propensity to induce weight gain and negatively influence lipid and glucose metabolism. Other agents considered to be minimally to moderately problematic in terms of weight gain and metabolic issues were quetiapine, risperidone, lithium, and valproate. Respondents reported that the profile of a bipolar agent in terms of weight gain and adverse metabolic effects was an important consideration in the management of bipolar disorder.

Conclusion: Although the study is limited by a low response rate and self-selection of respondents, clinicians who did respond were concerned about the risks of weight gain and metabolic disturbances in their patients treated with bipolar agents. For most parameters, such concerns were being integrated into clinical care. However, it appears that there is a need to increase clinicians’ appreciation of the importance of abdominal obesity and the need to monitor waist circumference. A growing recognition of the differences in weight-gain potential and adverse metabolic effects among agents appears to have had a definite impact on prescribing patterns in the management of bipolar disorder.     

A randomized, placebo-controlled study of zonisamide to prevent olanzapine-associated weight gain

Weight gain is commonly observed with olanzapine treatment. Zonisamide is an antiepileptic drug associated with weight loss. This study examined the effectiveness of zonisamide in preventing weight gain in 42 patients beginning olanzapine for bipolar disorder or schizophrenia. Each patient had a body mass index of 22 mg/kg or greater and was randomized to taking olanzapine with either zonisamide (n = 20) or placebo (n = 22) for 16 weeks. The primary outcome measure was change in body weight in kilograms from baseline. In the primary analysis using longitudinal regression, patients who received zonisamide had a significantly slower rate of weight gain and increase in body mass index than those who received placebo. The patients treated with zonisamide gained a mean (SD) of 0.9 (3.3) kg, whereas those treated with placebo gained a mean (SD) of 5.0 (5.5) kg; P = 0.01. None of the patients in the zonisamide group, compared with 7 patients (33%) in the placebo group, gained 7% of body weight or greater from baseline (Fisher exact test, P = 0.009). The zonisamide group, however, reported significantly more cognitive impairment as an adverse event than the placebo group (25% vs 0, respectively; P = 0.02). Zonisamide was effective for mitigating weight gain in patients with bipolar disorder or schizophrenia initiating treatment with olanzapine but was associated with cognitive impairment as an adverse event.     

Intermittent treatment with olanzapine causes sensitization of the metabolic side-effects in rats

The second generation antipsychotic drugs are effective treatments for psychotic disorders. Many of these compounds, including the drug olanzapine, have been associated with metabolic side-effects, including weight gain, impaired glucose tolerance and insulin resistance, which increase the risk of developing cardiometabolic disorders. Rodent models of olanzapine-induced metabolic side-effects have been used to study the physiology of these effects, but only at a single time point after drug treatment. The purpose of the present study was to examine longitudinal changes with chronic antipsychotic drug treatment. Adult female rats were treated with either olanzapine (15 mg/kg) or vehicle for five consecutive days each week, followed by a 48 h washout period. Animals were then challenged with either olanzapine (15 mg/kg) or vehicle, and fasting glucose and insulin values were recorded, as well as glucose clearance in the glucose tolerance test. Treatment with olanzapine was continued for 10 weeks, with weekly tests of metabolic indices. Rats treated acutely with olanzapine showed both glucose dysregulation and insulin resistance; for the group treated during the week with olanzapine, these effects did not change by the end of ten weeks of treatment. However, in the group of animals challenged only once per week with olanzapine, the metabolic side-effects markedly intensified with the passage of time, whereby glucose intolerance and insulin resistance increased significantly compared to both baseline values and all other treatment groups. This previously unreported sensitization phenomenon represents a novel finding that may have clinical implications for patients receiving intermittent antipsychotic drug dosing or with variable adherence to treatment.     

Comparison of the metabolic effects observed in patients treated with ziprasidone versus olanzapine

This study aimed to examine the impact of ziprasidone and olanzapine on QTc interval, weight and metabolic parameters in adults with schizophrenia and other psychoses. A retrospective cohort chart review was performed of 191 randomly selected patients who were being treated with ziprasidone or olanzapine in an integrated health care system. Significant differences on QTc interval were not observed. A significant weight gain was observed in olanzapine-treated patients (P<0.001) but not in the ziprasidone-treated cohort (P>0.05). Furthermore, adverse metabolic changes associated with olanzapine administration were significant with respect to effects on total cholesterol (P=0.01), triglycerides (P=0.05) and haemoglobin A1C (HbA1C) (P<0.05), whereas significant favourable metabolic effects were observed in ziprasidone-treated patients with regard to total cholesterol (P<0.05), low-density lipoprotein (LDL) (P<0.01), high-density lipoprotein (HDL) (P<0.05) and HbA1c (P<0.05). Our results suggest that these two atypical antipsychotics are safe and well tolerated from a cardiovascular standpoint, with no differences in QTc interval prolongation being observed. Olanzapine-treated patients exhibited significant weight increases, whereas ziprasidone-treated patients exhibited weight loss. Olanzapine treatment was also associated with significant adverse effect on patient's lipid profile and HbA1c. These adverse metabolic effects were not observed in ziprasidone-treated patients although favourable effects were observed with regard to effect on total cholesterol, LDL, HDL and HbA1c.     

Attenuating effect of reboxetine on appetite and weight gain in olanzapine-treated schizophrenia patients: a double-blind placebo-controlled study

Rationale Search for safe and effective strategies to diminish weight gain associated with second generation antipsychotics (SGAs) is imperative. In the present study, we sought to replicate our preliminary findings, which indicated that coadministration of the selective norepinephrine reuptake inhibitor reboxetine attenuates olanzapine-induced weight gain. Materials and method Fifty-nine patients hospitalized for first-episode DSM-IV schizophrenic disorder participated in this randomized double-blind study. Reboxetine (4 mg/day; 31 patients) or placebo (29 patients) was coadministered with olanzapine (10 mg/day) for 6 weeks. Analysis was by intention-to-treat. Results Nine patients in each group prematurely discontinued the trial. Olanzapine/reboxetine-treated patients showed a significantly lower increase in body weight (mean = 3.31 kg, SD = 2.73) than their olanzapine/placebo-treated counterparts (mean = 4.91 kg, SD = 2.45). Significantly fewer olanzapine/reboxetine-treated patients gained at least 7% of their initial weight, the cutoff for clinically significant weight gain (6 [19.4%] of 31 patients vs 13 [46.4%] of 28 patients). Seven (22.6%) olanzapine/reboxetine-treated patients compared to only one patient (3.6%) in the olanzapine/placebo group revealed no weight change or even modest weight loss. Appetite increase was significantly lower in the olanzapine/reboxetine than olanzapine/placebo group and was correlated with attenuation of weight gain. Reboxetine addition was safe and well tolerated. Conclusions The results confirm that coadministration of reboxetine promotes a clinically meaningful attenuation of olanzapine-induced weight gain in schizophrenia patients. If substantiated in long-term studies, along with behavioral management and diet counseling, reboxetine may have a clinical utility in controlling SGA-induced weight gain.     

Objective and subjective efficacy as well as tolerability of olanzapine in the acute treatment of 120 patients with schizophrenia spectrum disorders

The aim of the present study was to evaluate the objective and subjective efficacy as well as tolerability of olanzapine in acute treatment of schizophrenia spectrum disorders under naturalistic non-selective conditions. Inpatients with schizophrenia spectrum disorders, consecutively admitted over an 18-month period, treated with olanzapine, were included. Diagnoses were made according to ICD-10 criteria based on repeated clinical assessments. Efficacy and tolerability of olanzapine were assessed at baseline and at the end of inpatient acute treatment including Positive and Negative Symptom Scale (PANSS), Clinical Global Impression, subjective assessments, UKU and biological investigations. One hundred and twenty non-selected patients who met ICD-10 criteria for schizophrenia (73%), schizophreniform disorder (14%) or schizoaffective disorder (13%) were treated with olanzapine 15.3+/-5.2 mg/day. Baseline severity (PANSS total mean score 102.2) was higher compared to various admittance studies (PANSS total mean score 86-90). In 32% of patients (n=38), olanzapine treatment was discontinued, mainly because of inefficacy for positive (89%, n=34) and/or negative (95%, n=36) symptoms and/or because of adverse events (37%, n=14). Response rates as improvement in PANSS total score (after > or =3 weeks of treatment) of > or =20%, 30% or 40% were 68%, 55% and 35%, respectively. Response rates in post-hoc defined treatment resistant patients were not significantly different from non-refractory patients. Sedation (26%) was the most common side-effect, followed by weight gain (22%). With regards to subjective efficacy, 30% of the patients were not satisfied with the efficacy of olanzapine, while only 6% of the patients reported a not satisfying subjective tolerability. According to duration of olanzapine treatment, the results for patients, who remained in hospital, revealed a faster increase of weight compared to admittance studies (7 kg in 14 weeks versus 7 kg in 38 weeks). Olanzapine has been found to be effective and tolerable, also under naturalistic acute treatment conditions. Compared to previous double-blind admittance studies, patients had a higher severity of illness at entry and a lower > or =40% PANSS total score response rate. By contrast to previous results, mean dose of olanzapine was similar for multiple- and first-episode patients, and weight gain was more severe. The results underline the need of Phase IV studies for the assessment of clinical antipsychotic efficacy and tolerability.     

Nizatidine treatment and its relationship with leptin levels in patients with olanzapine-induced weight gain

It has been reported that nizatidine may reduce the weight gain in schizophrenic patients receiving olanzapine treatment. Previous studies have demonstrated a relation between olanzapine-induced weight gain and serum leptin levels. Therefore, in the present study, it was planned to investigate the efficacy of nizatidine on the treatment of olanzapine-induced weight gain, and if available, whether leptin levels were associated with reductions in weight gain. Of the patients with schizophrenia on olanzapine treatment, 59 who gave informed consent entered a 3 month open-label screening period. Of them, 35 patients (59%) showed weight gain in excess of 2.5 kg. These patients were randomly divided into two groups; olanzapine plus nizatidine (group I) and olanzapine plus placebo (group II) for an 8-week double-blind phase. The patients were evaluated at the baseline and at week 8 with respect to the positive and negative syndrome scale, body mass index, weight and serum leptin levels. In the open-label period, olanzapine led to a considerable marked increase in weight and in serum leptin levels. There was no statistically significant difference between the groups with respect to weight at the beginning of the 8-week double-blind treatment period. Throughout the 8 week double-blind period, in group I, the weight decreased by 4.5 +/- 2.2 kg ( p<0.05). In contrast, weight increased in group II by a mean of 2.3 +/- 0.9 kg ( p>0.05). The leptin levels decreased by 4.4 +/- 2.3 ng/ml in group I ( p<0.01), and increased by 1.8 +/- 0.6 ng/ml in group II ( p>0.05). These changes were accompanied by changes in the leptin levels in both groups I and II. It is concluded that leptin seems to be strongly associated with olanzapine-induced weight gain and that nizatidine treatment may reduce the weight gain and the correlated leptin levels in patients with schizophrenia on olanzapine treatment.     

Leptin and leptin receptor gene polymorphisms and increases in body mass index (BMI) from olanzapine treatment in persons with schizophrenia

OBJECTIVE: The objective of the current investigation was to determine the relationship between polymorphisms of the leptin system (leptin gene and leptin receptor) and olanzapine-induced weight gain in persons with schizophrenia. DESIGN: Pharmacogenetic association reanalysis of a longitudinal, open label, six week, fixed dose trial of olanzapine response and adverse effects. SUBJECTS: Thirty-seven males and females with clinically symptomatic schizophrenia (age, 23-52) meeting DSM-IV criteria. MEASUREMENTS: Baseline and endpoint weight, BMI, olanzapine dose, plasma levels, and psychopathology measures were completed in a prior study. These subjects were subsequently genotyped for the -1548 G/A polymorphism of the leptin gene and the Q223R polymorphism of the leptin receptor. The relationship between alleles at each locus, olanzapine plasma levels, and percent change in body mass index (BMI) from baseline were conducted. RESULTS: Genotypes and alleles for each locus were not individually associated with olanzapine-induced weight gain in this study population. Changes in BMI from baseline increased significantly in persons with olanzapine plamsa levels >20.6 ng/mL for subjects carrying at least one G allele at both candidate loci compared to those who did not have a G allele at each (P = 0.049). CONCLUSIONS: This study suggests that genetic variability in the leptin gene and leptin receptor may predispose some individuals to excessive weight gain from increased exposure to olanzapine.     

Metformin for olanzapine-induced weight gain: a systematic review and meta-analysis

Olanzapine is an atypical antipsychotic that is useful in schizophrenia and bipolar affective disorder, but its use is associated with troublesome weight gain and metabolic syndrome. A variety of pharmacological agents has been studied in the efforts to reverse weight gain induced by olanzapine, but current evidence is insufficient to support any particular pharmacological approach. We conducted a systematic review and meta-analysis of randomized controlled trials of metformin for the treatment of olanzapine-induced weight gain. Systematic review of the literature revealed 12 studies that had assessed metformin for antipsychotic-induced weight gain. Of these, four studies (n= 105) met the review inclusion criteria and were included in the final analysis. Meta-analysis was performed to see the effect size of the treatment on body weight, waist circumference and body-mass index (BMI). Weighted mean difference (WMD) for body weight was 5.02 (95% CI 3.93, 6.10) kg lower with metformin as compared with placebo at 12 weeks. For waist circumference, the test for heterogeneity was significant (P= 0.00002, I²= 85.1%). Therefore, a random effects model was used to calculate WMD, which was 1.42 (95% CI 0.29, 3.13) cm lower with metformin as compared with placebo at 12 weeks. For BMI, WMD was 1.82 (95% CI 1.44, 2.19) kg m⁻² lower with metformin as compared with placebo at 12 weeks. Existing data suggest that short term modest weight loss is possible with metformin in patients with olanzapine-induced weight gain.     

A review of the safety and tolerability of aripiprazole

It seems that the efficacy of aripiprazole for treating schizophrenia is mediated through a combination of partial agonism at dopamine D2 and serotonin 5-HT1A receptors and antagonism at serotonin 5-HT2A receptors. Aripiprazole has also received approval for the treatment of bipolar disorder as adjunctive therapy or monotherapy (manic or mixed episodes) as well as an augmentation therapy of major depressive disorder (MDD) by the US FDA. The overall safety and tolerability of aripiprazole is favorable compared to other atypical antipsychotics across the approved indications. Aripiprazole showed a minimal propensity for clinically significant weight gain and metabolic disruption. However, extrapyramidal side effects, such as akathisia, are reported and may limit its clinical use in some cases, particularly in patients with bipolar disorder and MDD. This review focuses on the tolerability and safety of aripiprazole across a broad spectrum of psychiatric disorders while taking into consideration results from registrational studies as well as findings from studies in the naturalistic setting. In conclusion, whereas the comparative safety and tolerability of aripiprazole has not been systematically evaluated in comparator studies, tolerability and safety issues commonly associated with atypical antipsychotics such as weight gain and metabolic syndrome are less prominent with aripiprazole.     

Olanzapine: an atypical antipsychotic for schizophrenia

Olanzapine is a serotonin-dopamine receptor antagonist primarily used in the treatment of psychotic illnesses. It has been shown in numerous large trials to be as equally effective as haloperidol in the acute treatment and maintenance treatment of schizophrenia. However, olanzapine was shown to be more effective than haloperidol in the treatment of negative symptoms and to cause significantly fewer extrapyramidal symptoms. Furthermore, early reports suggest that olanzapine produces less tardive dyskinesia than haloperidol, though longer follow-up data are needed. Current studies have failed to demonstrate the efficacy of olanzapine in the treatment of refractory schizophrenia. One comparison trial of olanzapine versus risperidone has indicated similar efficacy. Clinical trials in acute mania have found olanzapine to be more effective than placebo. However, there is no role for olanzapine monotherapy in bipolar disorder given current studies. Although olanzapine has shown a low rate of extrapyramidal symptoms, it is not without adverse effects. Clinically significant weight gain has been noted with olanzapine in each of the large clinical trials. The degree of weight gain is similar to clozapine and probably greater than that observed with risperidone. The long-term medical consequence of atypical antipsychotic-induced weight gain is not known at this time. While generally considered first-line drugs from an efficacy and adverse effect standpoint, pharmacoeconomic studies are needed to justify the large acquisition cost of olanzapine compared to typical agents.     

Effectiveness of long-term aripiprazole therapy in patients with acutely relapsing or chronic, stable schizophrenia: a 52-week, open-label comparison with olanzapine

Objective To compare the long-term efficacy and safety of aripiprazole with olanzapine in patients with either acute relapsing or chronic, stable schizophrenia.Materials and methods A 52-week, open-label extension to a 26-week, multicenter, randomized, double-blind, placebo-controlled trial in patients with chronic schizophrenia. Patients who completed the initial treatment or who met the protocol definition of relapse after ≥2 weeks of double-blind treatment were randomized to aripiprazole (15–30 mg/day, n = 104) or olanzapine (10–20 mg/day, n = 110) for 52 weeks.Results Sixty-nine percent of patients completed the study. Efficacy improvements were similar between groups at endpoint, mean reductions in Positive and Negative Syndrome Scale (PANSS) Total scores from baseline for patients completing the study (observed cases) were similar in chronic stable patients (aripiprazole, −7.94; olanzapine, −7.36) and in patients with acute relapse (aripiprazole, −31.19; olanzapine, −29.55). Olanzapine-treated patients reported more extrapyramidal symptoms (EPS)-related adverse events (18%) than aripiprazole-treated patients (10%). No significant differences in EPS were seen between treatments at endpoint. Olanzapine was associated with significantly greater weight gain than aripiprazole at all time points (week 52 [LOCF]: +2.54 vs +0.04 kg; p < 0.001). Changes in fasting glucose and lipid levels at endpoint favored aripiprazole over olanzapine, with significant differences observed for total cholesterol, low- and high-density lipoprotein. While differences observed for changes in fasting glucose and triglycerides favored aripiprazole, they were not statistically significant.Conclusion Aripiprazole showed similar efficacy to olanzapine for long-term treatment of acutely psychotic and chronic, stable schizophrenia patients, with a lower liability for weight gain or increased lipid levels.     

Olanzapine: an atypical antipsychotic for schizophrenia

Olanzapine is a serotonin-dopamine receptor antagonist primarily used in the treatment of psychotic illnesses. It has been shown in numerous large trials to be as equally effective as haloperidol in the acute treatment and maintenance treatment of schizophrenia. However, olanzapine was shown to be more effective than haloperidol in the treatment of negative symptoms and to cause significantly fewer extrapyramidal symptoms. Furthermore, early reports suggest that olanzapine produces less tardive dyskinesia than haloperidol, though longer follow-up data are needed. Current studies have failed to demonstrate the efficacy of olanzapine in the treatment of refractory schizophrenia. One comparison trial of olanzapine versus risperidone has indicated similar efficacy. Clinical trials in acute mania have found olanzapine to be more effective than placebo. However, there is no role for olanzapine monotherapy in bipolar disorder given current studies. Although olanzapine has shown a low rate of extrapyramidal symptoms, it is not without adverse effects. Clinically significant weight gain has been noted with olanzapine in each of the large clinical trials. The degree of weight gain is similar to clozapine and probably greater than that observed with risperidone. The long-term medical consequence of atypical antipsychotic-induced weight gain is not known at this time. While generally considered first-line drugs from an efficacy and adverse effect standpoint, pharmacoeconomic studies are needed to justify the large acquisition cost of olanzapine compared to typical agents.     

Extrapyramidal symptoms related to adjunctive nizatidine therapy in an adolescent receiving quetiapine and paroxetine

Weight gain is a serious problem with recently introduced atypical antipsychotic agents. Nizatidine, a histamine2 (H2)-receptor antagonist, may help reduce this weight gain. To our knowledge, no adverse effects have been reported when nizatidine is given at recommended doses with atypical antipyschotic agents. We describe, however, an adolescent who was receiving quetiapine and paroxetine for schizophrenia and depression, and developed extrapyramidal symptoms (EPS; parkinsonism and akathisia) after taking nizatidine for weight loss. Based on a report of another patient who developed EPS after taking higher-than-recommended doses of nizatidine, we reviewed the literature on treatment with H2-receptor antagonists for weight gain and on central nervous system adverse effects of nizatidine. Nizatidine may be effective for reducing weight gain associated with both medical and psychiatric conditions. Its safety profile is usually benign, although some patients may develop serious adverse effects, such as EPS and delirium. Therefore, the drug is recommended for short-term management of weight gain associated with atypical antipsychotic agents. Patients receiving nizatidine therapy should be monitored closely for development of EPS, particularly when high doses are prescribed.