Schizophrenia risperidone-induced

Ziegenbein M, Kropp S. Risperidone-induced long-term weight gain in a patient with schizophrenia. Aust NZ J Psychiatry 2004 38 175-6. 

Chouinard G, Vainer JL, Belanger M-G, et al. Risperidone and clozapine in the treatment of drug-resistant schizophrenia and neuroleptic-induced supersensitivity psychosis. Prog Neuro-Psychopharmacol Biol Psychiatry 1994 18 1129-1141. 

The addition of paroxetine 20 mg/day to risperidone 4— 8 mg/day in 10 patients with schizophrenia produced a 45% increase in plasma concentrations of risperidone and its active metabolite, 9-hydroxyrisperidone (270). One of the patients developed signs of drug-induced Parkinson s disease following the addition of paroxetine. 

The behavioral despair of mice forced to swim without escape is measured by their immobility during a retest under the same conditions. Immobility in the forced swim test (FST) is reversed by antidepressant drugs (137), whereas PCP enhances the immobility. Pretreatment with clozapine and risperidone, as well as the 5-HT, antagonists, mianserin and ketanserin, attenuated the PCP-induced increase in immobility, whereas haloperidol and antidepressants have no effect (138,139). The PCP enhancement of the FST may provide a more selective animal model for the negative symptoms of schizophrenia. 

Combined use of ChEI with neuroleptic and antidepressant medication Although the successes of most pharmacological treatments for autistic adults are limited, combining medications may prove to be more effective. A study by Wang et al., 2007 examined the synergistic effect of risperidone and galantamine on the phencyclidine-induced mouse model of schizophrenia. Similar to autism, schizophrenic patients suffer from cognitive defects and impaired memory function. 

Haematologic A case of recurrent neutropenia on a combination of paliperidone long-acting injection and oral risperidone in a 45-year-old male with schizophrenia, alcohol dependence and hepatitis C cirrhosis is reported [196 ]. It is postulated that as drug-induced neutropenia may be dose-related the combination and effectively the greater exposure to risperidone and paliperidone contributed to the development of the blood dyscrasia. 

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