Attention deficit hyperactivity disorder (ADHD) may be well known, but there is still a great deal that scientists don't know about it.

The U.S. Food and Drug Administration has issued a warning about a serious potential side effect of methylphenidate products (e.g. Ritalin, Concerta, and Daytrana) used to treat attention deficit hyperactivity disorder (ADHD).

Earlier this month, the FDA reviewed the labels for ADHD medication and decided to add two new side effects to the drugs  Focalin and Focalin XR .

While ADHD has been known to cause academic challenges for children and adolescents, tic disorders that sometimes accompany ADHD can affect a youth's social confidence as well.

The Adderall / Focalin  question has long faced newly diagnosed ADHD (attention deficit hyperactivity disorder) patients and their parents. So can science, with the precision of its methods and the weight of its authority, decide the matter?