Ritalin causes depression years later

Maybe that's the plan of Big Pharma -- feed 'em Ritalin today, and you'll have a new customer for antidepressant drugs a few years down the road.

• Pre-adolescent rats given the popular ADHD drug Ritalin are more likely to show signs of depression in adulthood, according to a Harvard study.
• The study suggests stimulants, at least in the normally developing brain, can have unsuspected effects in adulthood.
• The findings also underscore the importance of an accurate diagnosis for Attention Deficit Hyperactivity Disorder.
• William Carlezon, director of McLean Hospital's Behavioral Genetics Laboratory and associate professor of psychiatry at Harvard Medical School, presented the findings in Puerto Rico at the annual meeting of the American College of Neuropsychopharmacology.
• Carlezon said that because there are no animal models for ADHD, the young rats in the Harvard study were normal.
• "We know that depression occurs more often in adults with ADHD," said Dr. Peter Jensen, director of the Center for the Advancement of Children's Mental Health at Columbia University Medical Center.
• "What we don't know is whether it's because the disorder wasn't treated when it should have been, or was treated and the depression is a consequence of treatment, or it's a result of ADHD itself."
• The animals were exposed to Ritalin during the same developmental stage as a human between ages 4 and 12.
• In adulthood, the animals were given tests to tap the brain circuits thought to trigger ADHD symptoms --- hyperactivity, impulsivity, difficulty focusing.
• The tests showed "the animal's brain reward system is altered" by drug treatment in pre-adolescence, Carlezon said.