Effects of risperidone on polydipsia in chronic schizophrenia patients

Relationship between polydipsia and antipsychotics: A systematic review of clinical studies and case reports

OBJECTIVE

This systematic review aimed to elucidate the relationship between polydipsia and antipsychotics.

METHODS

We systematically searched MEDLINE, Embase, and PsycINFO, and included clinical studies and case reports on polydipsia induced or improved by antipsychotics.

RESULTS

We identified 61 articles: 1 double-blind randomized controlled trial (RCT), 4 single-arm trials, 1 cross-sectional study, 3 case series, and 52 case reports. The double-blind RCT demonstrated no significant difference in improvement in polydipsia between olanzapine and haloperidol. Two single-arm trials showed that polydipsia improved during clozapine treatment, whereas the other 2 showed that risperidone did not improve polydipsia. The cross-sectional study showed the prevalence of hyponatremia with first-generation antipsychotics (FGAs: 26.1%) and second-generation antipsychotics (SGAs: 4.9%). Two case series reported that clozapine improved polydipsia; the other one indicated that patients with polydipsia who were treated with FGAs had schizophrenia (70.4%) and mental retardation (25.9%). Of 90 cases in the case reports, 67 (75.3%) were diagnosed with schizophrenia. Of 83 cases in which antipsychotic treatment started before the onset of polydipsia, 75 (90.3%) received FGAs, particularly haloperidol (n = 24, 28.9%), and 11 (13.3%) received risperidone. Among 40 cases in which polydipsia was improved following antipsychotic treatment, 36 (90.0%) received SGAs, primarily clozapine (n = 14, 35.0%).

CONCLUSIONS

Although the causal relationship between polydipsia and antipsychotics remains unclear because of the paucity of high-quality studies, antipsychotics with high affinity to dopamine D₂ receptors may be associated with an increased risk of polydipsia while clozapine may be effective for treating polydipsia.

Atypical antipsychotics and polydipsia: a cause or a treatment?

Primary polydipsia (PP) is a frequent complication that affects many chronic schizophrenic inpatients. Due to possible lethal consequences, for example, hyponatremia, coma and death, it's fundamental for the physician achieving early diagnosis and treating this condition. The first step is identifying polydipsia by clinical, biochemical and pharmacological means. Nowadays, the pathophysiology of PP remains unclear, and this limits the possibility of detecting an appropriate drug treatment. Typical antipsychotics have been associated to a worsening of polydipsic behavior, while more recently atypical antipsychotics have been reported as being useful. However results are still mixed and controversial. It appears that risperidone and olanzapine are not clearly effective; clozapine may improve symptoms, although it is difficult to manage from a therapeutic point of view; quetiapine has been poorly studied so far, nonetheless it has given interesting results. Through a case study analysis, this report presents a brief, yet selective, overview of the current state of psychopharmacology in the treatment of PP with atypical antipsychotics in schizophrenia.

The treatment of psychogenic polydipsia with risperidone in two children diagnosed with schizophrenia

Polydipsia is a well-known phenomenon in adult psychiatry, but the literature regarding children is very limited. Just as the pathogenesis remains poorly understood, so does its management remain a clinical challenge. Data regarding the effect of risperidone on polydipsia are contradictory. We present case studies of remission of severe polydipsia with risperidone in two children.

Behavioral and medical treatment of chronic polydipsia in a patient with schizophrenia and diabetes insipidus

OBJECTIVE

This case report describes a novel outpatient behavioral treatment intervention for chronic polydipsia. The program was used in an effort to reduce excessive fluid intake in a woman with chronic paranoid-type schizophrenia who also had a diagnosis of diabetes insipidus.

METHODS

The 12-session individual behavioral intervention incorporated self-monitoring, stimulus control, coping skills training, and reinforcement components.

RESULTS

The patient engaged fully in the treatment program, and she successfully restricted her fluid intake. Her diabetes insipidus could therefore be treated with desmopressin, a medication that requires fluid restriction, and she experienced a concomitant reduction in polyuria and urinary incontinence.

CONCLUSIONS

The outpatient behavioral intervention demonstrated promising outcomes in a chronically mentally ill patient whose polydipsia had underlying psychogenic and physiological components. This case highlights the efficacy of combining behavioral and medical interventions.

Risperidone failed to improve polydipsia-hyponatremia of the schizophrenic patients

The effect of risperidone on polydipsia-hyponatremia was evaluated in six hospitalized schizophrenic patients. The normalized diurnal weight gain (NDWG), urine-specific gravity (USG), urine and plasma osmolarity, and serum sodium were monitored during 9 months of risperidone treatment. The dose of risperidone (mean +/- SD=8.0 +/- 1.0, range=6-9 mg/day) was determined as approximately half of the haloperidol-equivalent dose of previous neuroleptics. Before risperidone treatment, the mean (+/- SD) BPRS score was 23.5 +/- 7.1; no significant improvement was observed after risperidone (22.0 +/- 7.5). The subjects showed relatively high serum prolactin before risperidone treatment (mean +/- SD=16.5 +/- 9.7 ng/mL), that was not significantly decreased by risperidone (14.2 +/- 7.9 ng/mL). The monthly means (+/- SD) of NDWG and USG before risperidone were 5.5 +/- 1.5 (%) and 1.002 +/- 0.001, respectively. These and other indices did not significantly improve throughout the study period. Although the sample size is relatively small, our preliminary data showed that risperidone might not be effective on polydipsia-hyponatremia of schizophrenic patients.

Novel antipsychotics and patient care in state hospitals

OBJECTIVE

To review and highlight the opportunities and challenges of pharmacologic advances in the use of antipsychotics for the state hospital system.

METHODS

A critical review was performed of studies published either as articles or abstracts, on the use of novel antipsychotics, particularly as they relate to the patient population within the state mental hospital system.

FINDINGS

The recent availability of new antipsychotic medications within state facilities has resulted in more progressive treatment, reduced recidivism (and consequently cost savings), and preliminary evidence of preferential and superior treatment response in specific patient subgroups (e.g., those with aggression). At the same time, inpatient pharmacy budget increases and uncertainty in guiding the use of novel antipsychotics have influenced the availability of these agents in state hospitals.

CONCLUSIONS

State hospital services have, by and large, embraced the developments in pharmacotherapy of schizophrenia. Optimal use of these new agents in this population requires additional information on their relative efficacy in specific patient subgroups.