WASHINGTON -- The FDA has withdrawn approval for a drug used to treat attention deficit hyperactivity disorder because it has been associated with liver problems, including death, agency officials said Monday. The move means drug manufacturers will no longer produce generic versions of pemoline, which was developed by Abbott Laboratories and sold under the name Cylert. Abbott discontinued the drug earlier this year, but generic versions have remained available. FDA is not recalling the drug, instead allowing pharmacies to sell their remaining stock as doctors still using it switch patients to alternative treatments, the agency said in a statement. The...