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medication-assisted treatment for substance use disorders

Co-Occurring Disorders


SAMHSA's 2002 report to Congress defines co-occurring disorders as:

Individuals who have at least one mental disorder as well as an alcohol or drug use disorder. While these disorders may interact differently in any one person (e.g., an episode of depression may trigger a relapse into alcohol abuse, or cocaine use may exacerbate schizophrenic symptoms), at least one disorder of each type can be diagnosed independently of the other.

This report to Congress estimated that seven to ten million individuals in the United States have at least one mental disorder as well as an alcohol or drug use disorder. Research and first-hand experiences in both the mental health and substance abuse treatment fields have led researchers and practitioners to understand that both disorders must be addressed and treated comprehensively for people with co-occurring disorders to fully recover.

SAMHSA's report to Congress also indicates that:

  • Co-occurring disorders may include any combination of two or more substance abuse disorders and mental disorders identified in the Diagnostic and Statistical Manual of Mental Disorders - IV (DSM-IV)
  • There are no specific combinations of substance abuse disorders and mental disorders that are defined uniquely as co-occurring disorders
  • Substance abuse and mental health problems (such as binge drinking by people with mental disorders) that do not reach the diagnostic threshold are also part of the co-occurring disorders landscape and may offer opportunities for early intervention
  • Both substance abuse disorders and mental disorders have biological, psychological and social components
  • Co-occurring disorders may vary among individuals and in the same individual over time
  • Both disorders may be severe or mild, or one may be more severe than the other

Defining Co-Occurring Disorders

The term "co-occurring disorders" typically refers to an individual having co-existing mental health and substance use disorders. There are a number of other terms that have been used to describe people in this category as well, including:

  • Dually diagnosed
  • MICA (mentally ill chemical abusers)
  • MISA (mentally ill substance abusers)
  • CAMI (chemical abuse and mental illness)
  • SAMI (substance abuse and mental illness)

Some of the most common psychiatric disorders seen in patients with co-occurring addiction issues include:*

  • schizophrenia
  • bipolar disorder
  • borderline personality disorder
  • major depression
  • anxiety and mood disorders
  • post traumatic stress disorder
  • pathological gambling
  • sexual and eating disorders
  • conduct disorders
  • attention deficit disorder

Patients being treated for mental health disorders also often abuse the following types of substances:*

  • alcohol
  • nicotine
  • opiates
  • sedatives
  • stimulants
  • marijuana
  • hallucinogens
  • prescription drugs

*From a Public Policy Statement on Co-Occurring Addictive and Psychiatric Disorders from the American Society of Addiction Medicine

Individualized Assessment and Treatment

The assessment for COD is integrated by analyzing and using data concerning one disorder in light of data concerning the other disorder. Chapter 4 in TIP 42 (CSAT, 2005) there are 12 specific steps in the integrated assessment process.

The 12-Step Assessment Process:

  1. Engage the Client
  2. Upon receipt of appropriate client authorization(s), identify and contact collaterals (family, friends, other treatment providers) to gather additional information
  3. Screen for and detect COD
  4. Determine severity of mental and substance use disorders
  5. Determine appropriate care setting (e.g., inpatient, outpatient, day-treatment)
  6. Determine diagnosis
  7. Determine disability and functional impairment
  8. Identify strengths and supports
  9. Identify cultural and linguistic needs and supports
  10. Identify additional problem areas to address (e.g., physical health, housing, vocational, educational, social, spiritual, cognitive, etc.)
  11. Determine readiness for change
  12. Plan Treatment

As with integrated screening and assessment, integrated treatment planning addresses both mental health and substance abuse, each in the context of the other disorder. Like assessment, treatment planning should be client-centered, addressing clients' goals and using treatment strategies that are acceptable to them.

From COCE Overview Paper #2: Screening, Assessment, and Treatment Planning for Persons With Co-Occurring Disorders.

Additional Information:

National Addiction Technology Transfer Center (NATTC)

SAMHSA Co-occurring Center of Excellence

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