WASHINGTON -The government on Monday said it will conduct the largest-ever study of whether drugs used to treat attention deficit and hyperactivity disorder also cause heart problems.Although medications like Shire (nasdaq: SHPGY - news - people )'s Adderrall and Johnson and Johnson (nyse: JNJ - news - people )'s Concerta raise patients’ blood pressure, government scientists say it is unclear whether this puts patients at increased risk of heart problems.
