Long term effects of psychostimulants

I found a very interesting article that was published in Neurobiology at the Chicago Medical School, the long-term effects of  ADHD-prescribed medications (stimulants) and “cognitive enhancers” on addiction gene regulation in comparison to that of other psychostimulants like cocaine are studied. For a long time the long-term effects of stimulants such as Adderall or Ritalin have been relatively unknown. ADHD affects approximately 7.8% of children aged 4–17 and 4.4% of adults in the US. In the last two decades the diagnosis of ADHD has increased so that the production and use of these psychostimulants has increased more than 16-fold.

            It is still debated whether or not the use of these medications is safe. “There is concern especially that long-term exposure to psychostimulants during the sensitive period of brain development may increase the risk for maladaptive neurobehavioral changes that may facilitate drug addiction and other neuropsychiatric disorders.” In cocaine, gene regulation plays a huge role in addiction because the molecular changes last a lifetime. This principle is what is causing worry over drugs like Adderall and Ritalin.  This study looks into the changes in gene regulation produced by psychostimulants in animal models.

            The findings summarized in the article show that psychostimulants like cocain and amphetamine produce changes in gene regulation in specific corticostriatal circuits. These effects are most evident in sensorimotor circuits, which are associated with habit formation and compulsive aspects of drug taking. At the bottom level, psychostimulants alter neurons of the “Go pathway”. Other studies on similar drugs show that they induce very similar molecular changes in the corticostriatal circuits.

Heinz Steiner, Vincent Van Waes, Addiction-related gene regulation: Risks of exposure to cognitive enhancers vs. other psychostimulants, Progress in Neurobiology, Volume 100, January 2013, Pages 60-80, ISSN 0301-0082, 10.1016/j.pneurobio.2012.10.001.

http://www.sciencedirect.com.ezaccess.libraries.psu.edu/science/article/pii/S0301008212001530?np=y