Potential drug-drug interaction in Mexican patients with schizophrenia.

OBJECTIVE: The aim of this study was to observe potential drug-drug interactions in the medication of Mexican schizophrenic patients. METHODS: We performed a retrospective and cross-sectional study that was carried out in a psychiatric clinic. Only the prescriptions of patients with schizophrenia whose diagnoses were based on the DSM-IV instrument were included in this study. The Drug Interactions Checker software ( http://www.drugs.com/drug_interactions.html ) was used in this study to analyse potential drug-drug interactions. RESULTS: In total, 86 of 126 patients were at risk of potential drug-drug interactions. Haloperidol and biperiden was the most common drug pair of 232 pairs evaluated. In our study, 13.8% of drug-drug interaction showed a major level of severity, whereas in 83.2%, the interaction was moderate. Finally, central nervous system (CNS) depression and anticholinergic effect were the main possible effects of drug-drug interaction. CONCLUSIONS: Our results revealed a high number of patients with schizophrenia receiving two or more drugs. The potential drug-drug interactions observed in the Mexican population are consistent with the concomitant use of antipsychotics, benzodiazepines, and antidepressants prescribed in schizophrenia that could cause central nervous system (CNS) depression and anticholinergic effect. Drug-drug interaction must be considered when the patient with schizophrenia is medicated.

Effects of Shakuyaku-Kanzo-to on Extrapyramidal Symptoms During Antipsychotic Treatment: A Randomized, Open-Label Study.

Extrapyramidal symptoms (EPS) are common adverse effects of antipsychotic treatment. This study examined the effects of the traditional Japanese herbal medicine (kampo) shakuyaku-kanzo-to on EPS during antipsychotic treatment. Twenty-two Japanese patients with psychiatric disorders who had developed EPS during antipsychotic treatment were randomly allocated to receive either shakuyaku-kanzo-to (7.5 g/d) or biperiden (3 mg/d) for 2 weeks. Extrapyramidal symptoms were evaluated using the Drug-Induced Extrapyramidal Symptom Scale (DIEPSS) and the Barnes Akathisia Rating Scale. Plasma levels of the monoamine metabolite homovanillic acid and serum prolactin levels were measured to investigate the mechanisms of action of shakuyaku-kanzo-to. Twenty of the 22 patients completed the study (10 patients in the shakuyaku-kanzo-to group and 10 patients in the biperiden group). There was a time effect on the Drug-Induced Extrapyramidal Symptom Scale total score (P < 0.01), suggesting that both shakuyaku-kanzo-to and biperiden decreased EPS. Notably, there was a time × drug interaction in dystonia, suggesting that shakuyaku-kanzo-to had a greater effect on dystonia compared with biperiden. No significant changes were observed in plasma homovanillic acid or serum prolactin levels after 2 weeks of treatment in either group. The effects of shakuyaku-kanzo-to on abnormal muscle tonus and dopamine D2 receptors may have contributed to improve EPS. These results suggest that shakuyaku-kanzo-to may be useful in decreasing EPS, especially dystonia, in patients undergoing treatment with antipsychotic agents.

Evaluation of the clinical efficacy of risperidone for untreated and treated cases of schizophrenia from various aspects.

The present study used a diversified approach to the evaluation of the clinical efficacy of the atypical antipsychotic risperidone, and the most appropriate method of switching the medication of patients undergoing alternative therapies; particularly, the widely used typical antipsychotic haloperidol. A study group of 120 patients with CYP2D6*1/*1 was subdivided into an untreated group of 20 (group A) and two groups of 50 previously treated patients (groups B and C) with haloperidol only, for more than 5 years. All patients began risperidone therapy at 2 mg/day b.i.d., increasing in increments of 2 mg to a maximum of 8 mg/day b.i.d., according to their respective PANSS score after each psychiatric evaluation. Group B underwent a tapered changeover in treatment, while group C was abruptly transferred to the new regimen. The results demonstrated that risperidone was effective in 81% of patients, regardless of previous treatment or the method of switching. Twenty patients interrupted their switch treatment for reasons of symptom aggravation. Risperidone was immediately effective against positive and negative symptoms in untreated patients; however, in the previously treated groups, it was initially effective against negative symptoms only; after a 2-week interval, positive symptoms also improved. The previously treated patients required the concomitant administration of an anticholinergic drug. The results of this study provide evidence that risperidone has a favorable profile with regard to efficacy and safety, which makes it a suitable treatment for schizophrenia. Risperidone therapy at the earliest possible stage shows optimal improvement in schizophrenia.

Combined treatment of schizophrenic psychoses with haloperidol and valproate.

In accordance with a previous study of adjuvant effects of the anticonvulsant carbamazepine (CBZ) on the neuroleptic treatment of schizophrenic psychoses, the effects of valproate (VPA) were tested in a randomly assigned double-blind, placebo-controlled study. Apart from a (statistically nonsignificant) psychopathological deterioration following discontinuation of VPA while on continuous neuroleptic mediation after four weeks and a statistically significant effect on "hostile belligerence", no overall therapeutic effects of the combination of haloperidol (HPD) with VPA were observed under controlled conditions. Unlike the results with CBZ, concomitant use of VPA led to an even higher consumption of haloperidol and biperiden and to a higher rate of extrapyramidal symptoms compared with the corresponding placebo group, although these differences did not attain statistical significance. In regard to use of the sedative neuroleptic chlorprothixene, there was a trend toward lower doses in the VPA group than in the placebo group. From these results, adjuvant effects like those of carbamazepine in the neuroleptic treatment of schizophrenic psychoses could not be confirmed for valproate in the present study. However, the trend toward lower doses of sedative medication and observed effects on "hostile belligerence" may indicate sedative and/or antimanic properties of valproate which have recently been demonstrated in several controlled studies.

Electroconvulsive therapy in Parkinson's disease

Para evaluar el efecto de la terapia electroconvulsivante (TEC) en pacientes con enfermedad de parkinson, Nosotros condujimos un estudio abierto con un curso de siete días de TEC en seis pacientes con enfermedades de parkinson idiopática. El deterioro motor mejoró en todos los casos durante TEC. Esta mejoría fue sostenida en tres pacientes después de 30 días, y persistió hasta el día 60 en un paciente; los registros de depresión mejoraron en cuatro pacientes y los niveles séricos de prolactina estuvieron elevados con cinco pacientes durante la TEC, disminuyendo establemente después. La respuesta a la TEC observada en las valoraciones motoras, congnoscitivas o afectivas pereció que era independiente una de otra. La mejor respuesta en la ejecución motora se observó en aquellos pacientes con una evolución más corta de la enfermedad y etapas más bajas de discapacidad. El método de TEC utilizado en este estudio fue seguro y evitó la apnea o las contracciones musculares. Nosotros concluímos que la electroterapia perece que induce una respuesta favorable aunque afímera en la enfermedad de parkinson. Sin embargo, se deben de hacer estudios controlados a largo plazo. Otros métodos de electroestimulación más selectivos de vías dopaminérgicas se deben de investigar.