Risperidone function

Many of the neuroleptics are a-adrenoceptor antagonists. Some, like chlorpromazine, block d postsynaptic receptors while clozapine (and risperidone) are as potent at 2 as D2 receptors. There is no evidence that either of these actions could influence striatal or mesolimbic function but NA is considered important for function of the prefrontal cortex and any increase in its release, achieved by blocking a2-mediated autoinhibition, might contribute to a reduction in negative symptoms and provide a further plus for clozapine (see Nutt et al. 1997). Centrally, however, most a2-receptors are found postsynaptically and their function, and the effect of blocking them, is uncertain. 

The vast majority of children with enuresis have normal uro-dynamics, including nocturnal bladder capacity. Functional bladder capacity can be estimated using this formula age in years + 2 = ounces of capacity. In some children, there appears to be a relationship between developmental immaturity (motor and language milestones) and enuresis, but the mechanism is unknown. Drugs like lithium, clozapine, risperidone,... 

Liver function test abnormalities are common. If aminotransferases are greater than three times the upper limit of normal, the antipsychotic should be changed to a chemically unrelated antipsychotic. These changes are less common with the SGAs but are reported with risperidone and clozapine. 

Cholestatic hepatitis has been reported with risperidone, and liver function test abnormalities (mostly transient) have been reported with olanzapine and clozapine. 

Renal/Hepatic function impairment-Treat with titrated doses of oral risperidone prior to initiating treatment with risperidone injection. The recommended starting dose is oral risperidone 0.5 mg twice daily during the... 

Hillert A, Maier W, Wetzel H, et al. Risperidone in the treatment of disorders with a combined psychotic and depressive syndrome—a functional approach. Pharmacopsychiatry 1992 25 213-217. 

Spollen JJ, Wooten RG, Cargile C, Bartztokis G. Prolactin levels and erectile function in patients treated with risperidone. J Clin Psychopharmacol 2004 24 161-6. 

Fagerlund, B., Mackeprang, T., Gade, A., Glenthoj, B. Y. 2004, Effects of low-dose risperidone and low-dose zuclopenthixol on cognitive functions in first-episode drug-naive schizophrenic patients, CNS.Spectr., vol. 9, no. 5, pp. 364-374. 

Moreover, according to Fiddle et al. (2000), after six weeks treatment with risperidone, the decreases in frontal lobe metabolism were more extensive. In other words, the risperidone produced a progressive chemical lobotomy with suppression of frontal lobe function. 

Chapter 1 examined three risperidone studies that confirm the braindisabling principles of psychiatric treatment by demonstrating that the drug causes a metabolic suppression in the frontal and temporal lobes (deactivation) that occurs in both normal persons and patients diagnosed with schizophrenia, and that this disabling effect correlates with a reduction in the expression of symptoms, such as hallucinations and delusions, that require a fully functioning brain. As previously noted, if measured, the effect would also correlate with an overall reduction in spontaneous mental activity and verbal expressions, which are common clinical phenomena in patients who experience psychomotor retardation in response to neuroleptics. 

Risperidone was a fairly potent inhibitor of glucose transport but was not very toxic for cells [in their tests] and olanzapine, a modest inhibitor of glucose transport, actually stimulated proliferation of neuronal cells. Haloperidol was toxic for [experimental cells], however, it did not affect glucose transport. On the other hand, this drug inhibited mitochondrial function (energy metabolism), which may explain its toxicity. 

Kline, A., Massucci, J., Zafonte, R., Dixon, C., DeFeo, J., Rogers, E. (2000). Differential effects of single versus multiple administration of haloperidol and risperidone on functional outcome after experimental brain trauma. Critical Care Medicine, 35, 919-924. 

An independent cross-sectional survey, not sponsored by the pharmaceutical industry, in schizophrenic outpatients clinically stabilized on a neuroleptic drug for a period of 6 months showed that quality-of-life measures and Global Assessment of Functioning did not differ significantly in patients taking typical neuroleptic drugs (n = 44) and novel ones (risperidone, n = 50 olanzapine, n = 48 quetia-pine, n = 42 clozapine, n = 46) (42). 

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