How to Assess a Dual Diagnosis

The term dual diagnosis refers to a person who has both substance abuse and mental health diagnoses. This is also sometimes referred to as co-occurring or co-existing disorders. Clinicians assessing people with dual diagnosis often face a substantial challenge, given the complexity of the interactions of these problems. Clinicians can, however, educate themselves about dual diagnosis issues and build their assessment skills.

Instructions

• 1

  Get the client's history. It is important to understand the client in terms of both substance use/abuse and psychiatric illness. A history of substance use should include details about all the substances that the client has used in her life, not just the current drug of choice, and should start with the age of first use. This history should also include past treatment as well as family history of addiction. Similarly, a history of mental illness should include when symptoms first began, duration, how they have impacted the client's life, as well as family history. A detailed history of these issues may be key in unraveling the interactions between substance use and mental illness.

• 2

  Diagnose the client using the Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-IV). The DSM-IV provides the diagnostic criteria for mental disorders as well as substance-use disorders, but it also can help a clinician differentiate between causal factors. For instance, the DSM-IV offers specific criteria for mental disorders that are substance-induced, and may indicate that a patient does not have a dual diagnosis. For instance, a person with a substance-induced psychotic disorder only has psychotic symptoms when she is under the influence. Therefore she would not likely have a diagnosis of a seperate psychotic disorder.

• 3

  Observe the client. In untangling the difference between substance and mental-health symptoms, a clinician needs to observe the client over time. It is unlikely that the clinician can make a proper diagnosis in a single interview. A client should start treatment for substance abuse first, rather than for mental illness. Once the client has had some time without using, it should be more apparent if symptoms were due to substance use or mental illness and the clinician can make a more accurate assessment and diagnosis.