McLEAN IN THE NEWS
Misdiagnosis of ADHD and prescription drug use in children may lead to later depression
March 24th, 2005
A new study published by William Carlezon, PhD, director of the Mailman Research Center's Behavioral Genetics Laboratory suggests that the misdiagnosis of attention-deficit hyperactivity disorder (ADHD) combined with prescription drug use in children may lead to a higher risk of developing depressive symptoms in adulthood. This work is among the first to examine the effects of early Ritalin exposure on behavior and brain function during later periods of life.
Carlezon and his collaborator, Susan Andersen, PhD, examined the effects of exposing rats to Ritalin during early development on behaviors later in life. They exposed normal rats to twice-daily doses of Ritalin during a period that is equivalent to approximately 4 to 12 years of age in humans. Examining the behavior during adulthood, Carlezon and Andersen conducted several types of tests that all showed the animals had a reduced ability to experience pleasure and reward, particularly when it was measured by sensitivity to cocaine. In addition, they found that the animals exposed to Ritalin during pre-adolescence were more prone to express despair-like behaviors in stressful situations (such as swim tests) as adults.
Overall, the animals showed more evidence of dysfunctional brain reward systems and depressive-like behaviors in adulthood.
Attention-deficit hyperactivity disorder is a serious medical problem for children and their parents. While Ritalin is an effective medication that improves the quality of life for many children with ADHD, accurately diagnosing and identifying the correct treatment regimen for the disorder is essential, especially when considering health effects that can last through adulthood. These findings are critical because they suggest that Ritalin can have long-term consequences on normal-functioning brains and are particularly relevant when considering the difficulty in correctly diagnosing children with ADHD.