When a child is diagnosed with a pervasive development disorder they are soon to learn that the medical model has few options or choices. Sometimes drugs are the first and only choice.
These medications make it clear that they are not curing the diagnosis (autism, ADD, ADHD); they are only targeting a symptom of a much more complex disorder. Most often, when drugs are prescribed, they are intended to address specific symptoms including behavioral issues, anxiety or depression, mood swings (including bipolar disorder), obsessive compulsive disorder, attention issues and hyperactivity.
Not everyone with an autism spectrum disorder, ADD or ADHD has the same symptoms, and not all symptoms can be treated with pharmaceuticals. All of the pharmaceuticals have the potential for side effects.
Some, nearly all when prescribed for autism, ADD and ADHD, are prescribed "off label" which means for purposes other than that for which they were approved. No pharmaceutical comes without risk.