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Concurrent Disorders Centre for Addiction
and Mental Health

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Concurrent Disorders

What are concurrent disorders?​

Concurrent disorders is a term used to refer to co-occurring addiction and mental health problems. It covers a wide array of combinations of problems, such as anxiety disorder and an alcohol problem, schizophrenia and cannabis dependence, borderline personality disorder and heroin dependence and bipolar disorder and problem gambling.

Concurrent disorders are also sometimes called:

  • dual disorders
  • dual diagnosis (However, in Ontario, this term is used when a person has an intellectual disability and a mental health problem.)
  • co-occurring substance use and mental health problems 

​These problems can co-occur in a variety of ways. They may be active at the same time or at different times, in the present or in the past, and their symptoms may vary in intensity and form over time.

People often ask, “Which came first: the mental health problem or the substance use problem?” This is a hard question to answer. Often it is more useful to think of them as independent problems that interact with each other.

What are the signs & symptoms of concurrent disorders?

There is no one symptom or group of symptoms that is common to all combinations.The combinations of concurrent disorders can be divided into five main groups:

  • substance use + mood and anxiety disorders, such as depression or panic disorder
  • substance use + severe and persistent mental health disorders, such as schizophrenia or bipolar disorder
  • substance use + personality disorders, such as borderline personality disorder, or problems related to anger, impulsivity or aggression
  • substance use + eating disorders, such as anorexia nervosa or bulimia.
  • other substance use + mental health disorders, such as gambling and sexual disorders.

What are the cause & risk factors of concurrent disorders?

There is no simple cause of concurrent disorders. Mental health problems and substance use problems can affect each other in several ways:

    • Substance use can make mental health problems worse.
    • Substance use can mimic or hide the symptoms of mental health problems.
    • Sometimes people turn to substance use to “relieve” or forget about the symptoms of mental health problems.
    • Some substances can make mental health medications less effective.
    • Using substances can make people forget to take their medications. If this happens, the mental health problems may come back (“relapse”) or get worse.
    • When a person relapses with one problem, it can trigger the symptoms of the other problem.

    A person with concurrent disorders will often have more serious medical, social and emotional problems than if he or she had only one condition. Treatment may take longer and be more challenging.

    What is the treatment for concurrent disorders?​ 

    Clients have the best success when both problems are addressed at the same time, in a co-ordinated way. The treatment approach usually depends on the type and severity of the person’s problems. He or she might receive psychosocial treatments (individual or group therapy) or biological treatments (medications), or often both.

    Although the overall treatment plan should consider both mental health and substance use problems, it is sometimes best to treat one problem first. For example, most people who have concurrent mood and alcohol disorders are likely to recover better if the alcohol disorder is treated first.

    Integrated trea​tment 

    Clients with severe concurrent mental health and substance use problems may need integrated treatment. Integrated treatment is a way of making sure that treatment is smooth, co-ordinated and comprehensive for the client. It ensures that the client receives help not only with the concurrent disorders, but also in other life areas, such as housing and employment. Ongoing support in these life areas helps clients to:

    • ​maintain treatment successes​​​​
    •  prevent relapses
    • ensure their basic life needs are being met.

    Integrated treatment works best if the client has a stable, trusting, long-term relationship with one case facilitator. This person is a health care professional, such as a case manager or therapist. Even though one person is responsible for overseeing the client’s treatment, the client may work with a team of professionals, such as psychiatrists, social workers and addiction therapists.

    If all the treatment services are not in one location, two or more programs may work together to co-ordinate treatment. For example, a therapist in an addiction program might ask new clients questions to see if they also have mental health problems. If the clients do, the addiction program could either: 

      • treat the mental health problems, or
      • refer clients to a mental health agency and work with that agency. Therapists at both agencies would keep in touch about the clients’ progress.

      Concurrent Substance Use and Mental Health Disorders: An Information Guide © 2004, 2010 Centre for Addiction and Mental Health​​

      Where can I find help, treatment and support for concurrent disorders?​​​

      Treatment and support are available for people living with drug use problems and addictions: 

      Treatment from CAMH

      Help for families from CAMH

      Ontario Drug and  Alchol Helpline (open 24/7 for treatment anywhere in Ontario)  

      Where can I find more information related to concurrent disorders?

      A Family Guide to Concurrent Disorders (PDF)

      Concurrent Disorders 101 (online tutorial) Please Note:Your pop-up blocker must be turned off to view this tutorial​​​

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