Evaluation of the role of captopril on clozapine-induced cardiotoxicity and hematotoxicity in adult male albino rats

Clozapine (CLZ) is considered the most effective drug in treatment of resistant schizophrenia. However, its cardiotoxic effect has raised concerns about its safety. Captopril is a well-known angiotensin-converting enzyme inhibitor with unique antioxidant properties. The aim of this study was to investigate the protective effect of captopril against CLZ-induced myocarditis, and since both drugs have hematotoxic effects, this study aimed to clarify the effect of their combined use on the bone marrow. The study was conducted for 4 weeks on 50 adult male albino rats divided into five groups: group I (negative control), group II (positive control), group III treated with captopril 5 mg/kg/day, group IV treated with CLZ 25 mg/kg/day, and group V treated with captopril (5 mg/kg) 1 hour before CLZ (25 mg/kg/day). CLZ group showed a significant increase in serum troponin I, marked histopathological changes, and immunohistochemical staining of DNA degradation product 8-hydroxy-2-deoxy guanosine (8-OHdG). It significantly increased malondialdehyde level and decreased glutathione peroxidase. Captopril coadministration decreased the histopathological hallmarks and biochemical marker of myocarditis and attenuated CLZ effects on the oxidative stress parameters and 8-OHdG, suggesting its protective action against CLZ-induced myocarditis. Complete blood count and bone marrow evaluation was normal indicating that captopril, in the protective dose given, didn’t increase the risk of CLZ-induced hematotoxicity

Use of anticonvulsants as prophylaxis for seizures in patients on clozapine

OBJECTIVE

The aim of this study is to conduct a critical review of the literature regarding the use of anticonvulsants in the prophylaxis of clozapine-induced seizures, to examine the relationship of the latter with clozapine daily dose, serum concentration and other factors than dosage that effect clozapine blood concentration, and to make recommendations for the management of clozapine-induced seizures.

METHOD

A systematic review of English-language MEDLINE articles was undertaken.

CONCLUSIONS

Clozapine-induced seizures may occur at any dose; the risk increases with dose and goes up to 4% at ≥ 600 mg/day. Some authors have advocated that patients on that dose regimen have anticonvulsant added as a primary prophylactic measure. The author discusses the pitfalls of this recommendation and highlights that seizures are better predicted from serum concentration (1300 ng/ml) rather than dose alone, and that serum concentration is strongly influenced by sex, age, smoking habit, drug-drug interactions and variations in the 1A2, 2D6 and 3A4 genotypes. Anticonvulsants are not recommended as a primary prophylaxis for clozapine-induced seizures. When deemed necessary as secondary prophylaxis, the clinician's choice should consider drug-drug interactions that may increase/decrease clozapine serum concentration and lead to more side effects, including neutropenia/agranulocytosis and seizures, or compromise therapeutic response. Recommendations for primary and secondary prophylaxis of clozapine related-seizures are provided.

A Case Study: Treatment of Refractory Schizoaffective Disorder with Aripiprazole

Objective:

To report the use of aripiprazole in the treatment of refractory schizoaffective disorder.

Case Summary:

A 42-year-old African American male with a 10-year history of schizoaffective disorder decompensated while being treated with haloperidol decanoate 200 mg intramuscularly per month and valproic acid 500 mg twice daily. Upon admission, his Global Assessment of Function scale (GAF) score was 10 and his Mini-Mental State Examination (MMSE) score was 2. He was treated with an initial injection of haloperidol decanoate 100 mg and, thereafter, with haloperidol 5 mg orally twice a day. He remained refractory to haloperidol and, on day 14, chlorpromazine 150 mg/day was added. The patient continued to show no response. On day 20, oral aripiprazole 15 mg was substituted for haloperidol and chlorpromazine. Forty-eight hours later, the GAF score was 30 and the MMSE score was 18. Ninety-six hours after receiving aripiprazole, the GAF and MMSE scores were 40 and 26, respectively.

Discussion:

Aripiprazole has been approved for the treatment of schizophrenia and bipolar disorder; however, it has not been approved for treatment of schizoaffective disorder. Aripiprazole is a novel drug representing a new class of agents used for the treatment of psychosis. Aripiprazole is a partial agonist at the dopamine D2 and serotonin 5-HT1A receptors, but an antagonist at the serotonin 5-HT2A receptors.

Conclusions:

Aripiprazole may be useful in treatment of refractory schizoaffective disorder.