Substance misuse or abuse problems can be really difficult to identify in people who are suffering with a co-occurring mental illness. Similarly , vice versa is also true; identifying a mental illness is really difficult to identify in a person who abuses substance like drug or alcohol. The reason being, it is very complicated to understand their behavior and find out whether it is their addiction that is responsible for causing a mental illness or their mental illness is leading them to substance abuse.
Until the last decade or so, the problem of dual diagnosis was not recognized by healthcare or addiction treatment professionals. However, when it was recognized , it was found out that about 40 percent of substance abusers suffer from some sort of mental illness or instability. Some may suffer with severe mood swings while others may have depression. There are people who also suffer from memory losses and hallucinations, which is extremely difficult or almost impossible to treat. The patients may regain control over their lives but then they experience severe triggers and intense cravings to consume substance.