Q for Child Psychiatrists: Ritalin and Substance Abuse?

My limited understanding about our knowledge of alcohol, benzodiazepines and certain stimulants is that they  permanently change the brain. I think the reasoning is that the brain seeks to maintain homeostasis, thus, if a depressant like alcohol is used in excess,  the brain produces more stimulant receptors to compensate. Those receptors can go to "sleep" when alcohol use is curtailed but are not eliminated. That is why the term "sleeping tiger" is sometimes used to describe the disease of alcoholism and used as a caution to even the long term sober. It also  explains why the long term sober are often  hyper sensitive to substances upon relapse. A 10 bag a day heroin user who is sober and relapses years later can overdose on only one bag (which formerly would not even produce a high when he/she was active). It would not surprise me at all to know that stimulants prescribed to children with ADHD (such as Ritalin and Stratera) might also permanently effect brain chemistry in a way that would similarly make someone more susceptible to the effects of certain drugs later in life. I think the question of whether that might also make a child more prone to drug abuse or addiction as an adult is,  however, unclear and, I think, complicated and extremely worthy of research.