It is not uncommon for people who have problems with a psychological issue to also be plagued by a co-occurring substance abuse issue. In fact, it is more common than one would imagine and quite a few individuals presently in drug and alcohol rehabilitation centers in Eureka, California may have mental health issues which have just simply been undiagnosed. Treatment professionals at successful drug and alcohol rehab centers in Eureka know how to identify persons with co-occurring mental and drug and alcohol abuse disorders in hopes that these two concerns can be handled simultaneously while the person is in rehab. Because both must be resolved, the individual should not leave rehab until they are psychologically stable, not just off of drubs.