Use of cannabidiol in anxiety and anxiety-related disorders.

OBJECTIVE: Cannabidiol (CBD) has a proposed novel role in the management of anxiety owing to its actions on the endocannabinoid system. The purpose of this systematic review was to evaluate the current evidence on the safety and efficacy of CBD in anxiety and anxiety-related disorders. DATA SOURCES: A literature search was conducted on PubMed, Google Scholar, and International Pharmaceutical Abstracts from database inception through June 2019. A bibliographic search of relevant articles was also conducted. STUDY SELECTION: Articles published from case reports, case series, or randomized controlled trials on human subjects were included in the review if they examined the safety and efficacy of CBD therapy in anxiety and anxiety-related disorders. DATA EXTRACTION: Two reviewers independently extracted the following data from the articles: year of publication; study design; patient characteristics (sex; type of anxiety disorder; use of concomitant anxiolytic therapy); dosing strategy and route of CBD administration; and safety and efficacy outcomes. RESULTS: Eight articles were included in the review: 6 small, randomized controlled trials; 1 case series; and 1 case report. These studies examined the role of CBD in the anxiety response of healthy volunteers; in generalized anxiety disorder; in social anxiety disorder; and in the anxiety component of posttraumatic stress syndrome. No articles that evaluated CBD in panic disorder, specific phobia, separation anxiety, and obsessive-compulsive disorder were identified. In the studies, CBD was administered orally as a capsule or as a sublingual spray and as either monotherapy or adjunctive therapy. Doses varied widely, with studies employing fixed CBD doses ranging from 6 mg to 400 mg per dose. Various anxiety assessment scales were used in the studies to assess efficacy, with CBD demonstrating improved clinical outcomes among the instruments. In general, CBD was well-tolerated and associated with minimal adverse effects, with the most commonly noted adverse effects being fatigue and sedation. CONCLUSION: CBD has a promising role as alternative therapy in the management of anxiety disorders. However, more studies with standardized approaches to dosing and clinical outcome measurements are needed to determine the appropriate dosing strategy for CBD and its place in therapy.

Facilitators and Barriers to Noninvasive Ventilation Adherence in Youth with Nocturnal Hypoventilation Secondary to Obesity or Neuromuscular Disease.

OBJECTIVE: Many youth struggle with adherence to bilevel noninvasive ventilation (NIV), often shortly after initiation of treatment. Anecdotal evidence suggests youths with comorbid obesity struggle with adherence while youths with comorbid neuromuscular disease demonstrate better adherence rates. The objective of this study was to explore factors relating to bilevel NIV adherence, and to compare these between youths with underlying obesity or neuromuscular disease. METHODS: An exploratory qualitative approach was used to examine youth and caregivers' experiences with and perceptions of bilevel NIV. Semi-structured interviews (n = 16) of caregivers and youths were conducted. Youths 12 years and older with nocturnal hypoventilation diagnosed on polysomnography and managed with bilevel NIV, with either concurrent obesity or neuromuscular disease were included. Thematic analysis of interview data was conducted using qualitative analysis software. RESULTS: Factors associated with positive bilevel NIV adherence included previous encouraging experiences with therapy; subjective symptom improvement; familiarity with medical treatments; understanding of nocturnal hypoventilation and its consequences; family and health-care team support; and early adaptation to treatments. Factors associated with poor bilevel NIV adherence included previous negative experiences with therapy, negative attitude towards therapy; difficulty adapting; perceived lack of support from family or health-care team; fear/embarrassment regarding treatment; caregivers not being health-minded; technical issues; side effects; and a lack of subjective symptom improvement. CONCLUSIONS: The dimensions which most affect adherence to bilevel NIV are those which contribute to youths' conception of feeling "well" or "unwell." Adherence to treatment may hinge largely on the way in which NIV is initially experienced and framed. COMMENTARY: A commentary on this article appears in this issue on page 1355.

Electroacoustic and Potentiometric Studies of the Hematite/Water Interface.

The basic charging properties of nearly spherical hematite particles were studied by using potentiometric titration and the electroacoustic technique. Both the pH and the ionic strength dependence of the surface charge and the zeta-potential were studied in detail. For calculating the zeta-potential from mobility data a few different theories were used and obtained differences are discussed. At pH values higher than 7 and at high electrolyte concentrations (50 mM and 100 mM NaNO(3)), it was difficult to fit the mobility data by using the full mobility spectra including both magnitude and phase angle at several frequencies. In this regime the best fits were obtained by using a theory for aggregated complexes (porous particles). From potentiometric titrations in 0.01, 0.1, and 1.0 M NaNO(3), parameters for a 1-pK Basic Stern Model were determined. The model was used to examine the possibility of correlating the experimentally determined zeta-potentials to the model-calculated potentials at the Stern plane. Qualitatively, the model predicted the correct ionic strength dependence of the zeta-potentials, and there was also a rather good quantitative agreement at high ionic strengths (50 and 100 mM NaNO(3)). However, at lower ionic strengths the model predicted values up to 40% higher than those found from the electroacoustic study. Surface conduction behind the slip plane was discussed as a possible cause for this discrepancy. Copyright 2001 Academic Press.