Michaela Mayerová

Risperidone increases the cortical silent period in drug-naive patients with first-episode schizophrenia: A transcranial magnetic stimulation study.

Objectives: Schizophrenia is accompanied by impaired cortical inhibition, as measured by several markers including the cortical silent period (CSP). It is thought that CSP measures gamma-aminobutyric acid receptors B (GABAB) mediated inhibitory activity. But the mutual roles of schizophrenia as a disease and the drugs used for the treatment of psychosis on GABA mediated neurotransmission are not clear. Methods: We recruited 13 drug-naive patients with first-episode schizophrenia. We used transcranial magnetic stimulation to assess CSP prior to initiating risperidone monotherapy and again four weeks later. At the same time, we rated the severity of psychopathology using the Positive and Negative Syndrome Scale (PANSS). Results: We obtained data from 12 patients who showed a significant increase in CSP, from 134.20±41.81 ms to 162.95±61.98 ms (p=0.041; Cohen’s d=0.544). After the treatment, the PANSS total score was significantly lower, as were the individual subscores (p<0.05). However, no correlation was found between ΔCSP and ΔPANSS. Conclusion: Our study in patients with first-episode schizophrenia demonstrated an association between risperidone monotherapy and an increase in GABAB mediated inhibitory neurotransmission.

Severe acute dystonia/akathisia after paliperidone palmitate application - a case study

Currently, there are three second-generation long-acting injectable antipsychotics on the market at our disposal - risperidone, olanzapine, and paliperidone; a fourth, aripiprazole, may also soon be available. These modern second-generation antipsychotics, including their depot forms, could be regarded as relatively safe though rare, but more serious complications may appear.

Intensive high-frequency repetitive transcranial magnetic stimulation in schizophrenia: a case study.

A recent meta-analysisi from Shi et al1 demonstrated that repetitive transcranial ,agnetic stimulation (rTMS) has a moderate effect size in the treatment of negative symptoms in schizophrenia, with a treatment course of 15 days or more (1sesion per day.)

Influence of dose, gender, and cigarette smoking on clozapine plasma concentrations

Introduction Therapeutic drug monitoring (TDM) of clozapine is a very useful method for verifying both the correct intake and the interindividual variability of its metabolism, thereby avoiding the risk of toxicity. The purposes of this paper were to discover how many patients using clozapine in common clinical practice have clozapine plasma concentration (PC) levels in the proposed reference range and to identify factors that influence clozapine PC levels. Methods Our study included 100 inpatients (diagnosed with schizophrenia or schizoaffective disorder) taking standard doses of clozapine (100–700 mg/day). Clozapine concentration was measured by high-performance liquid chromatography. Correlations between doses and PC levels and the influence of smoking and gender on clozapine PC levels were calculated. Results A large number of the patients (67%) had PC levels outside the proposed reference range. The clozapine PC levels were influenced by dose, gender, and cigarette smoking. Conclusion The correlations between dose, gender, and cigarette smoking and clozapine PC levels highlighted by our study overlap other research. It was surprising to find such a large number of patients with clozapine PC levels outside the therapeutic range. This result suggests the importance of clozapine TDM due to misunderstood inter- and/or intraindividual variability or misestimated partial therapeutic compliance.

Aldosterone and aldosterone/cortisol ratio is higher in serum of long-term compared to first episode schizophrenia patients: A pilot study

We have previously shown that patients with severe depressive episode exhibit higher aldosterone concentrations compared to those with moderate depressive episode. The present study was undertaken to test the hypothesis that circulating concentration of aldosterone reflect the clinical state in patients with schizophrenia. The sample consisted of 36 hospitalized patients (25 men, 11 women) with the first episode or long-term course of schizophrenia. The severity of psychopathology was evaluated using the Positive and Negative Syndrome Scale (PANSS). Samples for measurement of serum aldosterone were obtained immediately after awakening. The results showed that serum aldosterone concentrations were lower in patients with the first episode compared to those in patients with long-term course of schizophrenia. Importantly, lower aldosterone concentrations observed in patients with the first episode were associated with more severe clinical symptoms as indicated by all subscales of PANSS. Serum cortisol concentrations did not differ between the groups, while the aldosterone/cortisol ratio showed similar pattern as aldosterone concentrations. The present pilot study suggests that circulating aldosterone in patients with schizophrenia may reflect the severity of clinical symptoms but in an opposite direction than in patients with major depressive disorder.

Asymptomatic Elevation of Amylase and Lipase After Olanzapine Treatment

Olanzapine, an atypical antipsychotic,has been considered one of the most efficient antipsychotic drugs, and it is the most frequently prescribed. It is categorized as a multiacting receptor targeted antipsychotic. The most significant adverse effects of olanzapine are metabolic: acute pancreatitis is one of the most serious adverse effects; fortunately, it does not occur very often. Koller et al1 found 51 cases,and at least 13 cases have been described more precisely. We present a case study of a young female patient with a very fast and high increase of amylase and lipase, who remained asymptomatic, immediately after olanzapine treatment.