Animal and human studies indicate that cannabidiol (CBD), a major constituent of cannabis, has anxiolytic properties. However, no study to date has investigated the effects of this compound on human pathological anxiety and its underlying brain mechanisms. The aim of the present study was to investigate this in patients with generalized social anxiety disorder (SAD) using functional neuroimaging. Regional cerebral blood flow (rCBF) at rest was measured twice using (99m)Tc-ECD SPECT in 10 treatment-naïve patients with SAD. In the first session, subjects were given an oral dose of CBD (400 mg) or placebo, in a double-blind procedure. In the second session, the same procedure was performed using the drug that had not been administered in the previous session. Within-subject between-condition rCBF comparisons were performed using statistical parametric mapping. Relative to placebo, CBD was associated with significantly decreased subjective anxiety (p < 0.001), reduced ECD uptake in the left parahippocampal gyrus, hippocampus, and inferior temporal gyrus (p < 0.001, uncorrected), and increased ECD uptake in the right posterior cingulate gyrus (p < 0.001, uncorrected). These results suggest that CBD reduces anxiety in SAD and that this is related to its effects on activity in limbic and paralimbic brain areas.

The Alcohol Use Disorders Identification Test (AUDIT) is an instrument used to screen for alcohol-related problems. It has been increasingly used in many different countries in both the original English-language version and its many translated versions. Because of the need for screening instruments of faster administration, shortened versions of the AUDIT have also been developed. This study was aimed at expanding the work by Berner and colleagues (2007) in an attempt to answer some remaining questions as well as to identify and evaluate studies on the validation of modified versions of the AUDIT, which have not been previously analyzed. In order to do so, we identified indexed articles published between 2002 and 2009 related to the psychometric qualities of the AUDIT by matching the keywords: alcohol, Alcohol Use Disorders Identification Test, and AUDIT. We found 47 articles that evaluated the AUDIT in different countries and in diverse health and community contexts, involving adolescent, adult, and elderly samples. The studies confirmed the validity and efficiency of the AUDIT in the identification of harmful use, abuse, and dependence of alcohol, both in the original version and in modified ones. The possibility of using brief and efficient versions is of great value, since certain health contexts demand faster assessment. The results also showed that the reduced versions have satisfactory psychometric qualities, sometimes with sensitivity values higher than those of the AUDIT itself. The studies analyzed confirm the efficiency of the AUDIT both in its original, reduced, and language-adapted versions in different contexts and cultures.

Background: Among the many cannabinoids in the cannabis plant, cannabidiol (CBD) is a compound that does not produce the typical subjective effects of marijuana. Objectives: The aim of the present review is to describe the main advances in the development of the experimental and clinical use of cannabidiol CBD in neuropsychiatry. Methods: A non-systematic search was performed for studies dealing with therapeutic applications of CBD, especially performed by Brazilian researchers. Results: CBD was shown to have anxiolytic, antipsychotic and neuroprotective properties. In addition, basic and clinical investigations on the effects of CBD have been carried out in the context of many other health conditions, including its potential use in epilepsy, substance abuse and dependence, schizophrenia, social phobia, post-traumatic stress, depression, bipolar disorder, sleep disorders, and Parkinson. Discussion: CBD is an useful and promising molecule that may help patients with a number of clinical conditions. Controlled clinical trials with different neuropsychiatric populations that are currently under investigation should bring important answers in the near future and support the translation of research findings to clinical settings.

This study aimed to assess the discriminative validity of the Brazilian version of the Patient Health Questionnaire (PHQ-9) and of its reduced version (PHQ-2). The sample consisted of 177 women (60 cases of depression and 117 noncases). The SCID-IV was used as the gold standard. For the PHQ-9, a cutoff score equal to or higher than 10 proved to be the most adequate for the screening of depression, whereas the best cutoff score for the PHQ-2 was found to lie between 3 and 4. The systematic use of these instruments in nursing and in the context of primary health care could favor the early detection of depression.

OBJECTIVE: Experimental evidence has suggested that drugs that enhance cannabinoid type-1 (CB1) receptor activity may induce anxiolytic and antidepressant effects, whilst the opposite has been reported with antagonists. Thus, the objective of the present review is to discuss the potential psychiatric side-effects of CB1 receptor antagonists, such as rimonabant, which has been recently marketed in several countries for the treatment of smoking cessation, obesity and associated metabolic disorders. METHOD: Literature searches were performed in PubMed and SciELO databases up to February 2009. The terms searched were "obesity", "rimonabant", "cannabinoids", "unwanted effects", "diabetes", "smoking cessation" and "side-effects". RESULTS: Clinical trials have revealed that rimonabant may promote weight loss in obese patients, although it may also induce symptoms of anxiety and depression. DISCUSSION: Patients taking CB1 receptor antagonists should be carefully investigated for psychiatric side-effects. These drugs should not be prescribed for those already suffering from mental disorders. Nevertheless, the development of new compounds targeting the endocannabinoid system for the treatment of several conditions would be necessary and opportune.