Risperidone nervous system

CIMETIDINE ANTIPSYCHOTICS -CHLORPROMAZINE, CLOZAPINE, HALOPERIDOL, OLANZAPINE, PERPHENAZINE, RISPERIDONE, SERTINDOLE, THIORIDAZINE, ZUCLOPENTHIXOL T plasma concentrations of these antipsychotics, with risk of associated adverse effects - Drugs Acting on the Nervous System, Antipsychotics Cimetidine is an inhibitor of CYP3A4 (sertindole, haloperidol, risperidone) CYP2D6 (chlorpromazine, risperidone, zudopenthixol, thioridazine, perphenazine) and CYP1A2 (clozapine, olanzapine, sertindole, haloperidol) Avoid concomitant use. Choose alternative acid suppression... 

Of 524 inquiries received by the National Poisons Information Service concerning new neuroleptic drugs over 9 months, only 45 cases involved overdose with a single agent (olanzapine, n — 10 clozapine, n — 8 risperidone, n — 10 sulpiride, n = 16) (503). There were no deaths or cases of convulsions. Cardiac dysrhythmias occurred only with sulpiride. Symptoms were most marked with clozapine most patients had agitation, dystonia, central nervous system depression, and tachycardia. Most of the patients who had taken risperidone were asymptomatic. 

Dopamine is a major catecholamine neurotransmitter in the central nervous system that has been implicated in the regulation of locomotor activity, emotion, cognition, and behavior reward and in neuroendocrine regulation [39]. Clinically, dopaminergic drugs (e.g., risperidone) that block or activate dopamine receptors are used to treat neurodegenerative, neuropsychiatric, and neurode-velopmental conditions such as Parkinson s, schizophrenia, bipolar disorder, and autism [40],... 

Casamenti et al. [1399] developed a method for screening 11 central nervous system drugs (phenobarbital, olanzapine, clozapine, risperidone, loxapine, haloperidol, imipramine, amitriptyline, fluoxetine, chlorpromazine, paroxetine) on a Cjg column (A = 230 nm) using a 20/11.7 water (0.4g tetramethylammonium perchlorate with 0.2 mL of 7% (m/m) HCIO4 to pH 2.8 with ammonia)/acetonitrile mobile phase. Keep in mind that perchlorates, when concentrated with some metals, are hazardous. Elution was complete in 35 min with good resolution for most compounds. Plots of the effects of mobile phase modifier level and percent acetonitrile on overall retention are presented. Linear ranges of 25-5000 ng/mL with detection limits of 10-250 ng/mL (analyte dependent) are reported. 

Nervous system Impaired sensorimotor function was observed in 33 antipsychotic drug-naive patients with schizophrenia after they were given risperidone (n = 29) or olanzapine ( = 4) mean doses at 6 and 26 weeks were 3.9 and 3.2 mg/day for risperidone and 11.3 and 15 mg/day for olanzapine [128. ... 

Nervous system A study comparing somnolence with asenapine, olanzapine, risperidone and haloperidol relative to placebo evaluated 10 clinical trials of patients with schizophrenia or bipolar disorder [36 -]. The duration and incidence of somnolence was greatest for asenapine and olanzapine (maximal for olanzapine) and with shorter time to onset than the other antipsychotics and placebo patients with bipolar disorder were the most sensitive. 

Nervous system A randomised, double-blind, crossover study of 12 healthy adults with risperidone demonstrated significant dose-dependent effects on balance control. This effect was observed at low doses with no clinically detectable extrapyramidal symptoms [249 -]. Pisa syndrome is a dystonia affecting cervical and lumbar musculature that has been reported with risperidone, paliperidone and chlorpromazine. A case is presented of a 31-year-old male with MS and FDD who developed Pisa syndrome after chronic risperidone treatment showed improvement with lurasidone, but recurrence with chlorpromazine [250 ]. Another case in a 23-year-old female with history of seizure due to periventricular focal nodular heterotopia occurring 12 months after risperidone treatment she was eventually managed on olanzapine and baclofen PSI ]. A case of persistent Parkinsonism in an 84-year-old male after 5 months of risperidone (2 mg per day) is reported [252 ]. Other dystonic phenomena reported with risperidone include dislocation of the temporomandibular joint [253 ]. 

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