People diagnosed with attention-deficit disorder are having trouble filling prescriptions for Adderall, Ritalin and other drugs, U.S. pharmacists say. Erin Fox, manager of the University of Utah\'s drug information service, said there have been recurrent shortages of Adderall for about two years, The Palm Beach (Fla.) Post reported. The problem appears to have become chronic since generic versions of the drug became legal earlier this year. Nirav Pate, who owns Robalo Pharmacy in Palm Beach County, said he is able to fill only a couple of prescriptions for Adderall a day. \"It\'s rationed out. The problem is big. It is huge,\" Pate said. \"This is one of the biggest shortages right now.\" Ruth Hughes, who heads Children and Adults with Attention Deficit/Hyperactivity Disorder, said federal regulators limit the manufacture of ADHD drugs because they are considered likely to be abused. She said that those with ADHD often need the drugs to live normal and safe lives.