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Brief Description

When two disorders or illnesses occur in the same person, simultaneously or one after another, they are called comorbid. Comorbidity also implies interactions between the illnesses that affect the course and prognosis of both. In particular, many people addicted to drugs are also diagnosed with other mental disorders and all illnesses must be treated. Although substance abuse disorders often occur concurrently with other mental illnesses, this does not me that one causes the other, even when one comes first.

Related Publications

Other Resources

Past information on many drugs of abuse is available on our Archives site.

Featured Publication

Featured Publication

Drugs, Brains, and Behavior - The Science of Addiction

As a result of scientific research, we know that addiction is a disease that affects both brain and behavior.

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