Abstract
Research has documented high levels of co-morbidity between mental illness and substance misuse. This essay explores clinical practice issues relating to ‘dual diagnosis’ substance misuse in bipolar disorder and depression. Such misuse is common in this population, and presents a number of challenges to clinicians. Those with substance misuse have more severe symptoms and an increased risk of relapse. Assessment is complicated by factors such as a lack of standardised measures specifically for use with dual diagnosis clients. The effectiveness of specific psychological interventions for this population is somewhat unclear, though integrated interventions where both problems are treated together are often used. Cognitive behaviour therapy has been used with depression and substance use though its effectiveness with bipolar is unclear, and motivational interviewing is often used as a supplement to this. Integrated group interventions are being developed and appear to be superior to groups focusing on substance use alone. Other approaches such as acceptance and commitment therapy are starting to be developed for use with dual diagnosis clients. A number of variables predict outcome from interventions, and there may be considerable gender differences which need to be taken into account. At present integrated dual diagnosis services are developing slowly within the National Health Service though there have been some notable service innovations in recent years. It is concluded that those with substance misuse in addition to bipolar disorder or depression need to be given special clinical consideration, though more research on how this can be effectively done is needed.