DSM-IV counts substance abuse as a psychiatric disorder, and research has shown that it is far more effective to treat substance abuse as a health issue than otherwise.

But I think we may have to agree to disagree here.

I think we're already agreeing for the most part: Substance abuse is a different thing than being addicted, you can't use the terms interchangeably.

The one is a mental problem, the other has to do with the brain in a very specific biochemical sense.

I think that for the most part there is plenty of overlap between the two in terms of the people that are afflicted but there is a direct biochemical reason behind being addicted to any drug that is not directly related to mental illness.

To clarify, addiction is a disease. According to Dr Drew Pinsky in an interview on "The Eyes of Nye" (yes, that's another Bill Nye show)

> The definition of a disease for me would be 'an abnormal physiological process brought on by a relationship between the genetics of the individual and the environment. That path of physiology would create a set of signs and symptoms that progress in a predictable way that we would call a 'natural history' and by affecting the natural history we create a predictable response to treatment [...] and addiction does fit that, but people get hung up on where the physiology goes wrong. They don't understand that it's a brain disease.