Donatella Moliterno

Understanding the pharmacokinetics of anxiolytic drugs

Introduction: Anxiety disorders are considered the most common mental disorders and they can increase the risk for comorbid mood and substance use disorders, significantly contributing to the global burden of disease. For this reason, anxiolytics are the most prescribed psychoactive drugs, particularly in the Western world. Areas covered: This review aims to analyze pharmacokinetic profile, plasma level variations so as the metabolism, interactions and possible relation to clinical effect of several drugs which are used primarily as anxiolytics. The drugs analyzed include benzodiazepines, anticonvulsants (pregabalin, gabapentin), buspirone, β-blockers and antihistamines (hydroxyzine). Regarding the most frequently used anxiolytic benzodiazepines, data on alprazolam, bromazepam, chlordesmethyldiazepam, chlordiazepoxide, clotiazepam, diazepam, etizolam, lorazepam, oxazepam, prazepam and clonazepam have been detailed. Expert opinion: There is a need for a more balanced assessment of the benefits and risks associated with benzodiazepine use, particularly considering pharmacokinetic profile of the drugs to ensure that patients, who would truly benefit from these agents, are not denied appropriate treatment. An optimal pharmacological approach involving an integrative pharmacokinetic and pharmacodynamic optimization strategy would ensure better treatment and personalization of anxiety disorders. So it would be desirable for the development of new anxiolytic drug(s) that are more selective, fast acting and free from the unwanted effects associated with the traditional benzodiazepines as tolerance or dependence.

Effect of quetiapine and norquetiapine on anxiety and depression in major psychoses using a pharmacokinetic approach: A prospective observational study

AbstractBackground: Quetiapine apparently differs from other antipsychotic drugs in terms of its antidepressant activity and efficacy in bipolar depression. The mechanism of this activity is unknown although it may be mediated by its metabolite N-desalkylquetiapine (norquetiapine). Objective: The aim of the study was to analyse the relationships between quetiapine and norquetiapine plasma concentrations and clinical improvement in depressive and anxious symptoms. Methods: This was a prospective observational study. Recruited patients were evaluated during a clinical post-acute phase. Patients were recruited from patients hospitalized in the Psychiatric Department of Ospedale Maggiore Policlinico of Milan, Italy. After discharge they were followed-up as outpatients. The study involved 41 outpatients (23 males, 18 females; age >18 years) diagnosed as affected by schizophrenia (17 patients), borderline personality disorder (eight patients) or bipolar depression (16 patients) on the basis of the Diagnostic and Statistical Manual of Mental Disorders, fourth text revision (DSM-IV-TR) criteria. Patients were prescribed 50–800 mg of quetiapine (Seroquel®). Patients were evaluated after discharge from the psychiatric department (baseline, T0), after 15 days (T1) and after 3 months (T2) using the Brief Psychiatry Rating Scale (BPRS) with particular reference to the dimensions of depression (items 5, 9 and 13) and anxiety (items 1, 2 and 6). Plasma quetiapine and norquetiapine concentrations were determined by means of high-performance liquid chromatography at T2. Results: There was a significant improvement in the mean BPRS total score, as well as in the dimensions of anxiety and depression. The bipolar patients only showed a significant curvilinear relationship described by a second-order polynomial model between the plasma norquetiapine/quetiapine concentration ratio and the improvement in depression at T2. There was a significant negative linear correlation between the norquetiapine/quetiapine ratio and anxiety in all of the patients. Conclusion: The results of this study confirm the efficacy of quetiapine on both anxious and depressive symptoms. Norquetiapine has a specific effect on anxiety and depressive symptoms, showing a correlation between plasma concentrations and clinical efficacy only in patients with bipolar depression.

Suicide attempts in schizophrenic patients: Clinical variables

INTRODUCTION Schizophrenia is associated with a significant risk of suicide: 40-50% of schizophrenic patients report suicidal ideation at some point in their lives, and 4-13% eventually commit suicide. In order to be able to predict and prevent suicide in schizophrenic patients, it is necessary to investigate and characterise suicide victims who meet the criteria for psychotic disorders and risk factors. METHODS The aim of this retrospective study was to verify the associations between suicide attempts (SAs) and the demographic and clinical variables of 106 patients who met the DSM-IV-TR criteria for schizophrenia. The patients were divided into two groups on the basis of the presence/absence of lifetime suicide attempts, and their main demographic and clinical characteristics were analysed and compared. RESULTS The patients with a history of SAs frequently had a duration of untreated psychosis (DUP) of ≥1 year (chi-squared test=9.984, df=1, p=0.0016). They also showed significant associations with the presence of a depressive dimension (chi-squared test=4.439, df=1, p=0.0351), hospitalisations before SAs (chi-squared test=25.515, df=1, p <0.001), and a family history of psychiatric disorders (chi-squared test=12.668, df=2, p=0.0018) or suicidal behaviours (chi-squared test=18.241, df=2, p=0.0001). Finally, they were more frequently prescribed typical antipsychotic agents. CONCLUSIONS The severity of psychiatric symptoms indicates a high risk of suicide in schizophrenic patients. Further prospective studies of larger samples should investigate the role of early interventions and atypical antipsychotic treatment in reducing the risk.

A single-blind, randomized comparison of olanzapine at a starting dose of 5 mg versus 20 mg in acute schizophrenia.

Acute psychotic episodes represent critical situations during the course of schizophrenia. Olanzapine (OLZ), a second-generation antipsychotic, is efficacious in acute settings at dosages of 5 to 20 mg/d, and it can be considered a first-line treatment for patients with an acute episode of schizophrenia. The aim of this study was to evaluate the efficacy and tolerability of OLZ at a starting dose of 5 mg versus 20 mg in acute schizophrenic patients and to compare titration versus nontitration. Fifty-one schizophrenic inpatients were randomly assigned to receive OLZ at 5 mg/d (26 patients, group 1) or 20 mg/d (25 patients, group 2) as a starting dosage during an exacerbation phase. In group 1, the OLZ dosage was increased to a mean dosage of 10.55 (± 4.00) mg/d. Group 2 received OLZ at a fixed dose of 20 mg throughout the hospitalization period. Olanzapine was significantly and clinically effective on Brief Psychiatric Rating Scale (BPRS), Positive and Negative Syndrome Scale, PANSS positive symptoms, and Hamilton Rating Scale for Depression in both groups. There were no significant differences between groups 1 and 2 in the percent improvement in BPRS, Positive and Negative Syndrome Scale, PANSS positive symptoms, PANSS negative symptoms, or Hamilton Rating Scale for Depression; but group 2 was significantly superior in the mean percent improvement in the BPRS items of anxiety (P < 0.001) and suspiciousness (P < 0.05). In conclusion, the higher doses evidence more efficacy on anxiety and suspiciousness, so it seems to be useful to begin therapy with a full dose of the drug to obtain the maximum effect without any significant side effects.

long-acting olanzapine in maintenance therapy of schizophrenia: A study with plasma levels

Abstract Introduction. This prospective study was performed to evaluate clinical efficacy and tolerability of olanzapine long-acting injection (OLZ-LAI) and the relation between OLZ plasma level (PL) and the clinical outcome in maintenance therapy of schizophrenia. Material and methods. Twenty-five chronic schizophrenic outpatients with age ranging from 18 to 65 years were included in this 9-month study. Patients were given a dosage of either 210 or 300 or 405 mg of OLZ-LAI every 28 days. Patients were evaluated at baseline and every four weeks by Brief Psychiatric Rating Scale (BPRS) and Positive and Negative Symptom Scale (PANSS); at the same time, PL of OLZ was determined. The metabolic profile (aspartate aminotransferase, alanine aminotransferase, high-density lipoprotein, low-density lipoprotein, total cholesterol, and glucose levels) was analyzed every two months. Results. BPRS and total PANSS showed a statistically significant improvement from T2 with a clinical stabilization of psychopathological picture. PL ranged from 4.0 to 78.9 ng/ml (mean 20.59 ng/ml ± 14.66 standard deviation). The coefficient of variation of PLs was related to clinical stabilization. No post-injection delirium sedation syndrome occurred. Conclusions. Our data reveal the efficacy of OLZ-LAI in maintenance treatment of schizophrenia at lower dosages also in comparison with that of oral therapy. OLZ-LAI seems to be useful for guaranteeing constant PL of the drug. A lesser variation of PL was the most predictable factor associated with maintenance of clinical benefit.