This narrative review article aims to update knowledge on the neuropsychiatric complications of nitrous oxide use and low vitamin B12. We consider common forms and uses of nitrous oxide (N2O) and review its mechanism of action, and then explore the potential impacts of use. In particular, neuropsychiatric effects mediated by low vitamin B12 are considered and the correct interpretation of laboratory results explored. This is of particular importance as where vitamin B12 is inactivated by chronic nitrous oxide use, blood test levels of vitamin B12 may not reflect the quantity of functional B12 in patients.

The Court of Protection has the legal jurisdiction to make decisions about people who lack capacity to make decisions themselves (in England and Wales). When hearing cases, evidence can be provided to the court by expert witnesses and professionals. The Court of Protection Rules 2017 inform the practice and procedure within the Court of Protection. This article reviews the judgment from a Court of Protection case that analyses the proper role of the expert witness in the court. In doing so the article provides guidance to authors of expert witness reports and reports under section 49 of the Mental Capacity Act 2005 submitted as evidence to the court.

This editorial introduces the first of two special issues of BJPsych Advances on neurodevelopmental disorders, including intellectual disability, autism spectrum disorder, attention-deficit hyperactivity disorder and epilepsy. This issue is intended to offer a clinical tool kit for mental health professionals giving guidance on assessment and management of these disorders and associated conditions, such as behaviours that challenge.

The four main Indian religions – Hinduism, Buddhism, Jainism and Sikhism – have several shared concepts about self and suffering, which are salient to the world-view of the followers of these faiths. Understanding the concepts of mind, self and suffering in these faiths can help clinicians build better rapport and gain deeper understanding of the inner world of patients of these faiths. This article highlights the broad cultural and religious beliefs of these groups, with the hope that increased knowledge among clinicians might lead to better therapeutic engagement.

We comment on Martin Curtice's article on expert and professional reports for the Court of Protection, which highlights the importance of ‘clear explanation’ in mental capacity assessment. We put the Court in a broader context of the Mental Capacity Act and summarise recent research and education that aims to help give clinicians working in England and Wales capacity assessment guidance that is clinically grounded, multi-perspectival and legally defensible.

A wide variety of neurological conditions may present first to a psychiatrist and it is important to be aware of these in differential diagnosis. A careful history, examination and a broad differential diagnosis can help set up an appropriate management plan – with room to change if things change in unexpected ways. In this article we explore common ground shared by psychiatry and neurology and show how incorporation of neurological knowledge can improve the practice of psychiatry. Using four fictional case vignettes of altered mental status we explore important neurological differential diagnoses which could present to the Psychiatrist.

We now recognise that withdrawal symptoms from antidepressants are common, and can be severe and long-lasting in some people. Many withdrawal symptoms overlap with symptoms of anxiety or depression, making it difficult to distinguish withdrawal from relapse. We describe how their onset soon after dose reduction, the association of psychological with physical symptoms, their prompt response to reinstatement, and their typical ‘wave’ pattern of onset, peak and resolution can help distinguish withdrawal symptoms from relapse. We also examine evidence that suggests that antidepressant withdrawal symptoms are misdiagnosed as relapse in discontinuation studies aimed at demonstrating the ability of antidepressants to prevent future relapse (relapse prevention properties). In these discontinuation studies people have their antidepressants stopped abruptly, or rapidly, making withdrawal symptoms very likely, and little effort is made to measure withdrawal symptoms or distinguish them from relapse. We conclude that there is currently no robust evidence for the relapse prevention properties of antidepressants, and current guidance might need to be re-evaluated.

The National Institute for Health and Care Excellence (NICE) informs us that the first-line treatments for behavioural and psychological symptoms of dementia (BPSD) are non-pharmacological. Although psychotropics used to be the main strategy in the management of behaviours that challenge, there has been an increase in the use of biopsychosocial formulations since 2010, and there are now over a dozen to choose from. However, many are overly focused on obtaining information about the agitation, and less specific about providing details of the actions required to manage the behaviours. The NICE guidelines too fail to provide specific guidance on which non-pharmacological approaches to use. This article argues for giving equal weight to both the collection of meaningful information and the development of ‘informed actions’, because it is the actions that lead to change. The article outlines a management programme providing a framework for the assessment, formulation and treatment of agitation in dementia. The work draws on theory, evidence-based practice and practice-based evidence to provide a model with sufficient structure and flexibility to be useful for clinicians across a range of settings and professional groups.

Clozapine is the only antipsychotic licensed for treatment of Parkinson's disease psychosis (PDP) but is infrequently used in the National Health Service because of obstacles to the integration of hospital-based neurological/geriatric services with clozapine clinics run by community mental health teams. This commentary points out the mismatch between NICE quality standards on antipsychotic treatment for PDP and current clinical practice. It suggests that forthcoming integrated care systems should be able to overcome these obstacles, enabling innovative models for providing clozapine treatment for PDP such as those described by Taylor et al, so that clozapine treatment becomes a right for patients and their families.

Genomic medicine is an evolving medical specialty that uses genomic information about an individual as part of their clinical care (e.g. for diagnostic or therapeutic decision-making). It has rapidly grown since the completion of the Human Genome Project in 2003. In England, the National Health Service's Genomic Medicine Service is considered to be the first national healthcare system to offer whole-genome sequencing as part of routine clinical care. Already, genomic medicine is making an impact in the fields of oncology, pharmacology, rare and undiagnosed diseases, infectious disease and neurology. In this article, we present a useful tool kit for clinicians working with individuals with intellectual disability, autism spectrum disorder and epilepsy. This article provides evidence for the importance of genetic testing, conveys an understanding of the range of genetic tests available and their diagnostic yields and how these apply to intellectual disability, autism spectrum disorder and epilepsy. Our simple tool kit gives information on when to refer to a clinical geneticist and where to find resources for clinicians and parents on genetic testing.

Attention-deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with a higher prevalence rate in people with intellectual disability compared with their peers without such disability. The classic presentation is that of inattention and/or hyperactivity and impulsivity, but these symptoms can manifest differently in people with intellectual disability. Despite a higher prevalence, the rate of diagnosis and treatment of ADHD in intellectual disability remains low. This article discusses the clinical presentation of ADHD in people with intellectual disability and the relationship between ADHD and other comorbid conditions, such as autism and bipolar disorder. Pharmacological and non-pharmacological interventions are discussed from a practical and a clinical point of view.

Values-based practice (VBP) is a framework of clinical theory and skills to facilitate a good process whereby the (often conflicting) values involved in clinical decision-making can be recognised and balanced productively. Many of these values come from the personal histories of the patient and of the clinician, and the traditions and history of psychiatry. New developments in science lead to increasing choice and increasing complexity of values. Therefore, psychiatrists will need more skills in this area, as reflected by the inclusion of VBP in the Royal College of Psychiatrists’ training curricula. This article describes some tools for understanding and navigating this value diversity in applying science to clinical practice during history taking.

Distinguishing the symptoms of antidepressant withdrawal from those of relapse is a complex issue that has an impact on a significant number of clinicians and patients. This commentary expands on several important points made by Horowitz & Taylor in their examination of this critically under-researched area and illustrates the relationships between symptoms, and how their onset may provide insights into their aetiology.

As we age, there are characteristic changes in our thinking, reasoning and memory skills (referred to as cognitive ageing). However, variation between people in the timing and degree of change experienced suggests that a range of factors determine individual cognitive ageing trajectories. This narrative review considers some of the lifestyle factors that might promote (or harm) cognitive health. The focus on lifestyle factors is because these are potentially modifiable by individuals or may be the targets of behavioural or societal interventions. To support that, the review briefly considers people's beliefs and attitudes about cognitive ageing; the nature and timing of cognitive changes across the lifespan; and the genetic contributions to cognitive ability level and change. In introducing potentially modifiable determinants, a framing that draws evidence derived from epidemiological studies of dementia is provided, before an overview of lifestyle and behavioural predictors of cognitive health, including education and occupation, diet and activity.

This article offers a selective review of memory and of issues relevant for a psychiatrist thinking about memory in a forensic context. It considers the development of our knowledge of memory, some of the ways in which memory can be erroneous and some evidence that this fallibility may sometimes be overstated. It concludes with a section on good practice in psychiatric assessment and in medico-legal work, looking at memory assessment, malingering/exaggeration and guidance for expert witnesses.

Triage wards were introduced as a new model of psychiatric in-patient care in 2004. However, there is limited evidence comparing them with the traditional in-patient models of care. This article reviews the history of triage wards, their principles, the evidence for this model (e.g. length of in-patient stay, readmission rates, staff and patient satisfaction) and the development of assessment wards based on the triage model of care. The evidence shows that the triage model has higher rates of rapid discharge, with a greater proportion of ‘acute care’ performed in the community with the support of home treatment teams. This leads to lower bed occupancy in the triage wards without increased rates of readmission or a worse patient experience of in-patient care. However, overall staff experience was better in the traditional model, given that staff satisfaction rates were lower on locality wards in settings with triage systems in place. Future research should explore the potential impact on home treatment teams, and the rates of serious incidents due to the high number of acutely unwell patients on triage wards.

No recent pandemic has had such a severe socioeconomic impact as COVID-19. Significant economic uncertainty and social restrictions have led to increased levels of stress for many. There has been increased social isolation, financial stress and alcohol intake, all of which can increase domestic abuse and other forms of household abuse. Increases in abuse in the home found in other public health emergencies and economic recessions can be seen now – reported UK domestic abuse rates have increased since the start of COVID-19. This article focuses on how COVID-19 and its anticipated aftermath exacerbate the risk factors for domestic abuse in the general population and discusses clinical implications for mental health practitioners in the UK. It aims to provide a point of learning based on previous disease outbreaks and recessions, with a focus on specific factors, such as unemployment and alcohol misuse, and how these contribute to increasing incidence and severity of abuse – and more importantly, how mental health professionals can mitigate these for patients, 1 in 3 of whom are estimated to have already experienced abuse before the COVID-19 pandemic.

The scientific study of human sexuality is now accepted as mainstream practice but early researchers in the field often attracted considerable criticism. Masters and Johnson were pioneers in observing and describing normal sexual function and consequently they provided unique insights into helping to understand sexual dysfunction. Their contribution to describing the physiological process of sexual response alongside potential psychological factors resulting in and maintaining sexual dysfunction is widely acknowledged. Their work continues to influence contemporary sexual medicine and psychosexual therapeutic practice.

Physical activity is a modifiable risk factor for several physical and mental health conditions. It is well established that people with severe mental illness have increased risk of physical health complications, particularly cardiovascular disease. They are also more likely to be physically inactive, contributing to the elevated cardiovascular and metabolic risks, which are further compounded by antipsychotic medication use. Interventions involving physical activity are a relatively low risk and accessible way of reducing physical health problems and weight in people with severe mental illness. They also have wider benefits for mental health symptoms and quality of life. However, many barriers still exist to the widespread implementation of physical activity interventions in the treatment of severe mental illness. A more concerted effort is needed to facilitate their translation into routine practice and to increase adherence to activity interventions.