Prolactogenic effects of risperidone in male patients--a preliminary study

Management Strategies for Antipsychotic-Related Sexual Dysfunction: A Clinical Approach

Antipsychotic medication can be often associated with sexual dysfunction (SD). Given its intimate nature, treatment emergent sexual dysfunction (TESD) remains underestimated in clinical practice. However, psychotic patients consider sexual issues as important as first rank psychotic symptoms, and their disenchantment with TESD can lead to important patient distress and treatment drop-out. In this paper, we detail some management strategies for TESD from a clinical perspective, ranging from prevention (carefully choosing an antipsychotic with a low rate of TESD) to possible pharmacological interventions aimed at improving patients' tolerability when TESD is present. The suggested recommendations include the following: prescribing either aripiprazole or another dopaminergic agonist as a first option antipsychotic or switching to it whenever possible. Whenever this is not possible, adjunctive treatment with aripiprazole seems to also be beneficial for reducing TESD. Some antipsychotics, like olanzapine, quetiapine, or ziprasidone, have less impact on sexual function than others, so they are an optimal second choice. Finally, a variety of useful strategies (such as the addition of sildenafil) are also described where the previous ones cannot be applied, although they may not yield as optimal results.

Prolactin serum levels correlate with inflammatory status in drug-naïve first-episode schizophrenia

OBJECTIVES

The present study was to examine the relationship between serum levels of prolactin and the inflammatory status in drug-naïve, first-episode schizophrenia patients with normal weight.

METHODS

Patients with normal weight, drug-naïve, first-episode schizophrenia and healthy controls were enrolled in the study. Serum levels of prolactin (PRL) were measured using electrical chemiluminescence immunoassay. Serum levels of interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were examined using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Sixty patients with normal weight, drug-naïve, first-episode schizophrenia and 60 healthy controls were enrolled. The schizophrenia group had higher serum levels of PRL, IL-1β, IL-6 and TNF-α compared with the control group. There was a gender difference of hyperprolactinemia in schizophrenia group. There were positive relationships between serum levels of PRL and serum levels of IL-1β, IL-6 and TNF-α within the schizophrenia group. Within the schizophrenia group, TNF-α was the strongest predictor among the three cytokines for serum levels of prolactin after controlling for gender, age, education, smoking status and disease duration.

CONCLUSIONS

Patients with normal weight, drug-naïve, first-episode schizophrenia present elevated serum levels of PRL, which might be related to the up-regulated inflammatory status in this patient population.

The effect of smoking status on the plasma concentration of prolactin already elevated by risperidone treatment in schizophrenia patients

Smoking prevalence for schizophrenic patients is higher than for the general population. Inter-individual variability in hyperprolactinemia induced antipsychotics particularly risperidone can be explained by smoking status to some extent. We therefore studied the effects of smoking status on the plasma concentration of prolactin. Subjects included 154 schizophrenia patients (61 males, 93 females) who had received 3 mg of risperidone twice daily for at least 4 weeks. Sample collections were conducted 12 h after the bedtime dosing. The plasma concentrations of prolactin in the females were significantly higher than in the males (117.6±69.3 ng/ml vs. 52.9±30.7 ng/ml, p<0.001). The mean (±SD) plasma concentrations of prolactin did not differ between smokers and nonsmokers in the males (59.5±31.2 ng/ml vs. 47.6±29.3 ng/ml, not significant (ns)), but there was a significant difference in the females (100.2±59.1 vs. 134.0±74.6, ng/ml, p<0.05). Multiple regression analyses including gender, plasma drug concentration and age revealed that the plasma concentration of prolactin positively correlated with gender (standardized beta=0.452, p<0.001) and negatively with age (standardized beta=-0.171, p<0.05) and smoking status (standardized beta=-0.232, p<0.01). These findings suggest that smoking status has an impact on prolactin concentration during risperidone treatment. However, further study is required to determine whether these findings have clinical implications.

Dose-dependent effects of adjunctive treatment with aripiprazole on hyperprolactinemia induced by risperidone in female patients with schizophrenia

Hyperprolactinemia is a frequent consequence of treatment with risperidone. Recent studies have suggested that aripiprazole, a partial dopamine agonist, reduces the prolactin response to antipsychotics. Thus, we examined the dose effects of adjunctive treatment with aripiprazole on the plasma concentration of prolactin in patients who had elevated prolactin levels because of risperidone treatment. Aripiprazole was concomitantly administrated to 16 female patients with schizophrenia receiving 2 to 15 mg/d of risperidone. Dosages of aripiprazole were gradually increased from 3 to 12 mg/d with 2- to 4-week intervals. Sample collections for prolactin were conducted before aripiprazole administration (baseline) and 2 to 4 weeks after the dose escalation of aripiprazole and just before next dose escalation. The samples were taken just before the morning dose. The plasma concentration of prolactin during aripiprazole administration (3, 6, 9, or 12 mg/d) was significantly lower than that at baseline. The mean (±SD) percent reductions at 3, 6, 9, and 12 mg/d were 35% ± 14%, 54% ± 17%, 57% ± 19%, and 63% ± 17%, respectively. However, neither the plasma concentration of prolactin nor the reduction ratio differed among the dosages of 6, 9, and 12 mg/d of aripiprazole. Three out of 8 patients with amenorrhea improved after 12 mg/d of aripiprazole. The present study suggests that adjunctive treatment with aripiprazole reduces the prolactin concentration that had been increased because of risperidone treatment. The effect occurs even when a low dosage (3 mg/d) of aripiprazole was used and achieves a plateau at dosages beyond 6 mg/d.

Prolactin fluctuation over the course of a day during treatments with three atypical antipsychotics in schizophrenic patients

Hyperprolactinemia is a frequent consequence of treatment with some antipsychotic agents. Although prolactin secretion varies over the course of a day and during psychological circumstances, there is little information in the literature regarding the time dependence of the prolactin response to antipsychotics. We evaluated prolactin levels in schizophrenic patients receiving risperidone (3 mg twice daily), olanzapine (10 mg twice daily), or perospirone (16 mg twice daily) for at least 4 weeks. The subjects were compared to matched healthy controls. Plasma sample collection for quantification of drug and prolactin levels was conducted before and 2, 4, 6, 8, and 12 h after the morning dosing. Prolactin concentrations before dosing during risperidone treatment were significantly higher than during treatment with olanzapine and perospirone in females. The daily fluctuation of prolactin concentration after perospirone treatment was larger than that observed after risperidone and olanzapine treatments. Areas under the plasma concentration-time curves was greatest in subjects treated with risperidone, followed by perospirone and finally by olanzapine. These findings suggest that daily fluctuations in prolactin concentration after perospirone treatment are larger than following treatment with risperidone and olanzapine. The plasma concentration of prolactin during perospirone treatment therefore depends on the time of sampling.

Association between dopamine-related polymorphisms and plasma concentrations of prolactin during risperidone treatment in schizophrenic patients

Hyperprolactinemia is an inevitable consequence of treatment with antipsychotic agents to some extent because prolactin response to antipsychotics is related to dopamine blockade. Recent studies have suggested that polymorphisms of the dopamine receptors are associated with therapeutic response to antipsychotics. Thus, we studied the effects of major polymorphisms of dopamine-related genes on plasma concentration of prolactin. Subjects were 174 schizophrenic patients (68 males, 106 females) receiving 3 mg twice daily of risperidone for at least 4 weeks. Sample collections were conducted 12 h after the bedtime dosing. Five dopamine-related polymorphisms (Taq1A, -141C ins/del for DRD2, Ser9Gly for DRD3, 48 bp VNTR for DRD4, Val158Met for COMT) were identified. The mean (+/-SD) plasma concentration of prolactin in females was significantly higher than males (54.3+/-27.2 ng/ml versus 126.8+/-70.2 ng/ml, p<0.001). No dopamine-related polymorphisms differed the plasma concentration of prolactin in males or females. Multiple regression analyses including plasma drug concentration and age revealed that plasma concentration of prolactin correlated with gender (standardized partial correlation coefficients (beta)=0.551, p<0.001) and negatively with age (standardized beta=-0.202, p<0.01). No correlations were found between prolactin concentration and dopamine-related polymorphisms. These findings suggest that plasma prolactin concentrations in females are much higher than in males but the dopamine-related variants are not predominantly associated with plasma concentration of prolactin.

Association between major Multidrug Resistance 1 (MDR1) gene polymorphisms and plasma concentration of prolactin during risperidone treatment in schizophrenic patients

An in vitro study has suggested that risperidone is a substrate of P-glycoprotein, which is coded by MDR1gene. The rate of P-glycoprotein efflux transport can mediate brain penetration of lipophilic drugs. We therefore studied the effects of major polymorphisms of MDR1 gene on plasma concentrations of prolactin. Subjects included 175 schizophrenic patients (68 males, 107 females) who were receiving 3 mg of risperidone twice daily for at least 4 weeks. Sample collections were conducted 12 h after the bedtime dosing. The plasma concentrations of prolactin in females were significantly higher than in males (54.3+/-27.2 versus 126.8+/-70.2 ng/ml, p<0.001). There was no difference in mean (+/-SD) plasma concentration of prolactin between C3435T genotypes [C/C, C/T, T/T; 62.3+/-33.3, 49.4+/-15.6, 53.2+/-33.2 ng/ml, ns] or G2677T/A genotypes [G/G, G/T or A, T or A/T or A; 58.0+/-27.7, 58.5+/-35.0, 46.1+/-20.7 ng/ml, ns] in males nor between C3435T genotypes (123.6+/-65.0, 127.8+/-79.2, 130.4+/-49.7 ng/ml, ns) or G2677T/A genotypes (123.3+/-67.0, 97.7+/-71.2, 144.9+/-69.9 ng/ml, ns) in females. Multiple regression analyses including plasma drug concentration and age revealed that plasma concentration of prolactin correlated with gender (standardized beta=0.540, p<0.001) and negatively with age (standardized beta=-0.183, p<0.01). No correlations were found between prolactin concentration and MDR1 genotypes. These findings suggest that prolactin concentrations in females are much higher than in males but the major MDR1 variants are not associated with the plasma concentration of prolactin.

A naturalistic, 9-month follow-up, comparing olanzapine and conventional antipsychotics on sexual function and hormonal profile for males with schizophrenia

Second generation antipsychotics have less influence on prolactin levels than conventional antipsychotics (CA), which are commonly associated with sexual dysfunction and hyperprolactinaemia. However, only a few studies have been conducted assessing these newer antipsychotics and sexual function/dysfunction. The aim of this study is to evaluate the sexual function and hormonal profile of male schizophrenic patients taking olanzapine or CA. Sixty-three inpatients with acute episodes of schizophrenia were randomly assigned to take either olanzapine, or go on conventional antipsychotic treatment. The Dickson-Glazer sexual functioning questionnaire was used to assess sexual functioning where serum prolactin, luteinizing hormone, follicle-stimulating hormone, total testosterone, free testosterone, and sex hormone-binding globulin concentrations were measured. All measurements were taken on discharge from the inpatient unit (baseline), and again at 3 and 9 months after discharge. Prolactin levels in the olanzapine group decreased more rapidly and were significantly lower than in the CA group after 3 months (12.1+/-6.3 microg/l, p=0.01; 18.1+/-11.2 microg/l, p=0.564, respectively). After nine months, there was a tendency toward normal levels in both groups, and the frequency of sexual complaints did not differ between the groups. This study showed no difference between olanzapine and conventional antipsychotics regarding sexual complaints in the treatment of schizophrenia, but did show a difference in the hormone level normalization rate.

A systematic review on clinical management of antipsychotic-induced sexual dysfunction in schizophrenia

INTRODUCTION

Sexual dysfunction frequently occurs in patients with schizophrenia under antipsychotic therapy, and the presence of sexual side effects may affect compliance. The aim of this study was to review and describe clinical findings relating to the appropriate management of such dysfunctions.

MATERIAL AND METHODS

The research was carried out through Medline (from 1966 to March 2005), PsycInfo (from 1974 to March 2005), and Cochrane Library (from 1965 to March 2005) and included any kind of study, from case reports to randomized trials.

RESULTS

The most common sexual dysfunctions found in the literature were libido decrease, difficulties in achieving and maintaining erection, ejaculatory dysfunction, orgasmic dysfunction, and menstrual irregularities. Thirteen papers were found: eight of them were open-label studies, four were descriptions of cases, and only one was a randomized clinical trial. All of them were short-term and had small sample sizes. The agents used were: bromocriptine, cabergoline, cyproheptadine, amantadine, shakuyaku-kanzo-to, sildenafil and selegiline.

DISCUSSION

There was no evidence that those agents had proper efficacy in treating the antipsychotic-induced sexual dysfunction. An algorithm for managing sexual dysfunction induced by antipsychotics is suggested as a support for clinical decisions. Since the outcome from schizophrenia treatment is strongly related to compliance with the antipsychotics, prevention of sexual dysfunction is better than its treatment, since there is a scarcity of data available regarding the efficacy of intervention to deal with these problems.

Sexual dysfunction and psychotropic medications

Psychotropic drugs are often associated with sexual dysfunction. The frequency of antidepressant-associated sexual dysfunction is greatly underestimated in clinical trials that rely on patient self-report of these adverse events. Direct inquiry reveals that delayed orgasm/ejaculation occurs in >50% and anorgasmia in at least one third of patients given selective serotonin reuptake inhibitors. Antidepressant-induced sexual dysfunction can be successfully managed. A different antidepressant without significant sexual effects, such as bupropion or mirtazapine, can often be substituted. Other strategies involve drug holidays or adjunctive therapy with drugs such as sildenafil. Dopamine antagonist antipsychotic drugs are most commonly associated with decreased libido. The newer atypical antipsychotics, with less effect on dopamine, are less commonly associated with sexual dysfunction. Sexual dysfunction is commonly reported with seizure disorders, and many anticonvulsant drugs affect levels of sex hormones. Because sexual dysfunction can be related to many factors, care must be taken to establish the patient's baseline sexual functioning before the initiation of psychotropic drug therapy and to rule out other etiologies before drugs are implicated as causative.

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.

Castration reduces the effect of serotonin-1A receptor stimulation on prepulse inhibition in rats

This study examined the interaction between hormones and serotonin-1A (5-HT1A) receptor modulation of prepulse inhibition (PPI) of the acoustic startle response. Male and female rats were gonadectomized; some castrated rats received testosterone- or estrogen-filled implants. Rats were randomly injected with saline or 0.02 or 0.50 mg/kg 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), a selective 5-HT1A receptor agonist. All rats showed a dose-dependent disruption of PPI in response to 8-OH-DPAT. In untreated castrated rats, this disruption was significantly reduced (33% compared with 78% in sham-operated rats). Testosterone treatment reversed this reduction, but estrogen was less effective. Ovariectomized and sham-operated rats showed similar PPI in response to 8-OH-DPAT. These data suggest that the effect of 8-OH-DPAT on PPI in male rats depends on circulating hormone levels, particularly testosterone.

A case series of eight aggressive young children treated with risperidone

The aim of this study was to examine the use of risperidone in routine clinical care for very aggressive young children. This is a retrospective medical chart review of patients age less than 6 years 11 months who were treated with risperidone for 1 to 10 months during the 1-year study period. Treatment response, side effects, and Clinical Global Impression (CGI) scores were identified. One hundred and five such young children were identified; 8 had been treated with risperidone (6 boys, 2 girls: mean age 4.9 +/- 0.8 years). Risperidone was used in combination with other psychotropic medications in 7 of the 8 children. The mean daily dose of risperidone was 1.25 +/- 0.27 mg. Seventy-five percent of the children were on concomitant lithium, valproate, or carbamazepine; 63% were on stimulants or alpha adrenergics. This was a highly comorbid group, with 7 children presenting with attention deficit hyperactivity disorder and 5 children with bipolar disorder not otherwise specified. The average baseline CGI severity was 5.5 (SD = 0.5), and at last visit it was 3.5 (SD = 0.5), p < 0.0001. Mean CGI improvement score was 1.9 (SD = 0.6). Adverse effects included significant weight gain (mean 5.5 +/- 4.9 kg, p < 0.05) in 6 patients. One child had hyperprolactinemia. Given the potential development of atherosclerosis in obesity and endocrine response in hyperprolactinemia, risperidone should be reserved for those children with severe aggressive behavior who failed multiple trials with other agents. Further controlled trials are needed.

What are the effects of antipsychotics on sexual dysfunctions and endocrine functioning?

The literature is reviewed and preliminary results of new studies are presented showing that treatment with classical antipsychotics, as well as risperidone, induces sexual dysfunctions in 30-60% of the patients. These antipsychotics also frequently induce amenorrhoea and galactorrhoea. Although comparative studies are rare, it is likely that prolactin-sparing antipsychotics, as recently shown in a randomized trial of olanzapine versus risperidone, induce less sexual side effects.From these studies, it becomes apparent that prolactin elevation induced by classical antipsychotics and risperidone is probably a factor in inducing sexual dysfunctions, amenorrhoea and galactorrhoea. The role of other factors inducing sexual dysfunctions like sedation, proportional, variant -blockade, testosterone, dopamine, and serotonin is discussed. Finally, it is concluded that sexual and hormonal effects of antipsychotics, although clearly important, are often neglected in research as in clinical practice. Lowering the dosage or switching to a prolactin-sparing antipsychotic often reduces sexual side effects, amenorrhoea, and galactorrhoea.

Understanding the new and evolving profile of adverse drug effects in schizophrenia

This article has reviewed the emerging side-effect profiles of second-generation antipsychotic medications. Although these medications have favorable extrapyramidal side-effect profiles, clinicians must be aware of their propensity to cause weight gain, glucose and lipid abnormalities, and cardiac and sexual side effects. If clinicians are proactive about warning patients about these side effects and appropriately monitoring them, further morbidity and mortality may be prevented in this patient population. Initial choices of medication should be made based on the relative side-effect profiles in light of a particular patient's medical status. In the future, new treatments may be developed, with even fewer side effects.

Effects of risperidone on conduct and disruptive behavior disorders in children with subaverage IQs

OBJECTIVE

To determine whether risperidone is effective in reducing symptoms of disruptive behaviors (such as aggression, impulsivity, defiance of authority figures, and property destruction) associated with conduct disorder, oppositional defiant disorder, and disruptive behavior disorder-not otherwise specified in children with subaverage IQs.

METHOD

The trial consisted of a 1-week, single-blind, placebo run-in period and was followed by a 6-week, double-blind, placebo-controlled period. One hundred ten children (aged 5-12 years inclusive) with an IQ of 36-84 with a disruptive behavior disorder and a score of at least 24 on the Conduct Problem subscale of the Nisonger Child Behavior Rating Form (NCBRF) were enrolled. Eighty percent of subjects had comorbid attention-deficit/hyperactivity disorder (ADHD). Risperidone doses ranged from 0.02 to 0.06 mg/kg per day. Subjects were rated on the NCBRF, Aberrant Behavior Checklist, Behavior Problems Inventory, Clinical Global Impressions (CGI), modified California Verbal Learning Test (CVLT), and a continuous performance task (CPT).

RESULTS

The intention-to-treat analysis of risperidone-treated subjects showed a significant (p < .001) reduction in mean scores (from 33.4 at baseline to 17.6 at end point; 47.3% reduction) versus placebo-treated subjects (mean baseline of 32.6 to 25.8 at end point; 20.9% reduction) on the Conduct Problem subscale of the NCBRF. Between-group differences in favor of risperidone were seen as early as week 1 and were significant at all post-baseline visits. Other subscales showed significant improvement with risperidone compared with placebo. CGI scale ratings of improvement showed highly significant gains for risperidone over placebo. A subanalysis demonstrated that the effect of risperidone was unaffected by diagnosis, presence/absence of ADHD, psychostimulant use, IQ status, and somnolence. Risperidone produced no changes on the cognitive variables (CPT/modified CVLT). The most common side effects included somnolence, headache, appetite increase, and dyspepsia. Side effects related to extrapyramidal symptoms were reported in 7 (13.2%) and 3 (5.3%) of the subjects in the risperidone and placebo groups, respectively (p = .245).

CONCLUSIONS

Risperidone appears to be an adequately tolerated and effective treatment in children with subaverage IQs and severe disruptive behaviors such as aggression and destructive behavior.

Effects of risperidone on gonadal axis hormones in schizophrenia

OBJECTIVE

To investigate the effects of risperidone on the hypothalamo-pituitary-gonadal (HPG) axis of chronic schizophrenic male inpatients medicated regularly.

METHODS

Subjects included six inpatients who were diagnosed according to the Diagnostic and Statistical Manual, Fourth Edition, criteria for schizophrenia, and were termed treatment-refractory. Each patient gave informed consent for the research involved in this study. The neuroendocrine studies were done before and during risperidone administration. Patients took a mean dose of risperidone 9.5 mg/d for a mean period of 64.2 days. Psychotic symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS).

RESULTS

Prolactin (PRL) increased significantly during risperidone administration. However, luteinizing hormone, follicle-stimulating hormone, and testosterone did not show significant difference between blood concentrations before and during risperidone administration. Scores of the BPRS total, thought disturbance factor, and tension decreased significantly during risperidone administration. Throughout the study, none of the patients experienced clinically significant problems associated with elevated PRL concentrations including gynecomastia and/or sexual dysfunction.

CONCLUSIONS

Addition of risperidone produced significant improvement of psychotic symptoms in treatment-resistant schizophrenic patients, and an increase in basal blood PRL concentrations, but not in basal blood HPG axis hormone concentrations. This preliminary result warrants further double-blind evaluation with a larger sample.

Use of the dopamine agonists bromocriptine and cabergoline in the management of risperidone-induced hyperprolactinemia in patients with psychotic disorders

Risperidone is a novel antipsychotic agent that blocks both dopaminergic and serotonergic receptors. In several reports, clinically significant hyperprolactinemia has been reported in patients on this agent. However, the optimal management of risperidone-induced hyperprolactinemia has not been clarified. We reviewed the records of 5 patients with psychotic disorders who were evaluated for risperidone-induced hyperprolactinemia. There were 4 females and 1 male patient, aged 30-45 yr. All patients had significant hyperprolactinemia, with prolactin (PRL) levels ranging from 65.5 to 209 microg/l. All but 1 of these patients had manifestations of hypogonadism. In these 4 patients, risperidone therapy was continued and the dopamine agonists bromocriptine or cabergoline were added. In 3 out of 4 patients, such additional therapy reduced the PRL level and alleviated hypogonadism. None of the patients treated with these agents had a worsening of psychosis. We conclude that risperidone can cause clinically significant hyperprolactinemia in patients treated with this drug. If risperidone therapy must be continued in such patients, addition of the dopamine agonists bromocriptine or cabergoline may successfully alleviate hyperprolactinemia and the associated manifestations without worsening psychotic symptoms.

Risperidone-associated hyperprolactinemia

OBJECTIVE

To compare the prolactogenic effects of risperidone, clozapine, and typical antipsychotic agents in an outpatient community-based psychiatric population.

METHODS

Prolactin and thyroid-stimulating hormone (TSH) concentrations were measured in 68 outpatients with schizophrenia who were receiving antipsychotic medications and were recruited from a community mental health clinic.

RESULTS

The percentage of women with increased prolactin concentrations was significantly greater in the risperidone group (100%, 12 of 12 patients) than in the clozapine group (25%, 1 of 4) (P = 0.0071) but not in comparison with the typical antipsychotic agent group (83%, 5 of 6) (P = 0.333). The percentage of men with increased prolactin concentrations was significantly greater in the risperidone group (94%, 17 of 18) than in the clozapine group (18%, 3 of 17) (P<0.0001) and in comparison with the typical antipsychotic agent group (27%, 3 of 11) (P = 0.0003). The mean prolactin concentration (all ng/mL +/- standard deviation) was also significantly higher in patients taking risperidone (women, 125.0 +/- 56.6; men, 37.3 +/- 23.9) than clozapine (women, 22.0 +/- 25.9; men, 13.3 +/- 22.4) (female patients, P = 0.0004; male patients, P<0.0001) or typical antipsychotic agents (women, 69.0 +/- 59.8; men, 13. 3 +/- 9.1) (female patients, P = 0.036; male patients, P = 0.0003). In the risperidone group, gender affected prolactin level, with women having higher concentrations than men, but the duration of therapy did not. In this group, prolactin was inversely dependent on age. No difference was noted in TSH concentrations between medication groups.

CONCLUSION

Risperidone is a potent inducer of hyperprolactinemia in outpatients with schizophrenia in a community population. The higher and more frequently increased prolactin concentrations caused by risperidone could adversely affect patient health and compliance.

Impact of Antipsychotics on Geriatric Patients: Efficacy, Dosing, and Compliance

People today are living longer. Old age is the number one risk factor for dementia, which is often associated with behavioral disturbances and psychosis as well as cognitive and memory impairment. Elderly persons with dementia-particularly those who are agitated or aggressive-are often placed in nursing homes and consequently treated with antipsychotic medications. Most of the studies of antipsychotic efficacy and safety have been conducted in young schizophrenic patients, but there are differences in dosing schedules, efficacy, and compliance when these drugs are used in elderly patients with dementia and psychosis. A review of both nonpharmacologic and pharmacologic treatment is herewith presented for the treatment of elderly dementia patients, especially those living in long-term care facilities.

The effects of olanzapine, risperidone, and haloperidol on plasma prolactin levels in patients with schizophrenia

BACKGROUND

There is relatively little comparative information on elevations in plasma prolactin level (PRL) with conventional versus novel antipsychotic agents.

OBJECTIVE

This paper examines the comparative effects on PRL of olanzapine, risperidone, and haloperidol based on data from 3 multicenter, double-blind, randomized clinical trials. Magnitude of response, dose dependency, time course, effects of sex and age, and response to switching from haloperidol to olanzapine are assessed.

METHODS

The effects of olanzapine, risperidone, and haloperidol on PRL were assessed in patients with schizophrenia or related psychoses participating in 3 double-blind clinical trials: (1) a 6-week acute trial comparing olanzapine 5 to 20 mg/d (n = 1,336) and haloperidol 5 to 20 mg/d (n = 660), with a 1-year, open-label olanzapine extension for responders; (2) a 54-week study comparing olanzapine 5 to 20 mg/d (n = 21), risperidone 4 to 10 mg/d (n = 21), and haloperidol 5 to 20 mg/d (n = 23) in early illness; and (3) a 28-week study comparing olanzapine 10 to 20 mg/d (n = 172) and risperidone 4 to 12 mg/d (n = 167).

RESULTS

PRL elevations were significantly greater with risperidone than with either olanzapine or haloperidol in study 2. and significantly greater than with olanzapine in study 3 (all, P < 0.001). PRL elevations were significantly greater with haloperidol than with olanzapine in study 1 (P < 0.001 ). A dose-response relationship was not consistently confirmed with any of the drug treatments. Risperidone-associated PRL elevations peaked relatively early in treatment. In haloperidol- and risperidone-treated patients, the mean change in PRL was greater in women than in men. PRL decreased significantly when treatment was switched from haloperidol to olanzapine.

CONCLUSIONS

This side-by-side analysis of 3 independent studies suggests that with the 3 antipsychotic drugs studied, PRL is elevated moderately by olanzapine (mean change, 1-4 ng/mL), intermediately by haloperidol (mean change, approximately 17 ng/mL), and strongly by risperidone (mean change, 45-80 ng/mL). No consistent dose-response relationship was observed, and the time course and sex-dependency of the response differed between the 3 agents. Patients with haloperidol-induced hyperprolactinemia may benefit from a switch to olanzapine. Long-term studies examining the health consequences of chronic hyperprolactinemia during antipsychotic treatment are needed.

A history of antipsychotic drug development

The history of antipsychotic drug development has had a long and torturous course, often based on chance findings that bear little relationship to the intellectual background driving observations. In 1891, Paul Ehrlich observed the antimalarial effects of methylene blue, a phenothiazine derivative. Later, the phenothiazines were developed for their antihistaminergic properties. In 1951, Laborit and Huguenard administered the aliphatic phenothiazine, chlorpromazine, to patients for its potential anesthetic effects during surgery. Shortly thereafter, Hamon et al. and Delay et al. extended the use of this treatment in psychiatric patients and serendipitously uncovered its antipsychotic activity. Between 1954 and 1975, about 15 antipsychotic drugs were introduced in the United States and about 40 throughout the world. Thereafter, there was a hiatus in the development of antipsychotics until the introduction of clozapine treatment in the United States in 1990 opened the era of "atypical" antipsychotic drugs, which show a reduced potential to induce extrapyramidal symptoms (EPS), an increased efficacy for the negative symptoms of schizophrenia, no elevation of prolactin after chronic use (except risperidone), and, at least for clozapine, effectiveness in some patients previously regarded as treatment-refractory. This review describes the available atypical antipsychotic drugs and their characteristics, and concludes by highlighting those in the pharmaceutical "pipeline."