Lipitor, and other cholesterol-fighting drugs like it, will carry new instructions about risks. Paul Sakuma/AP hide caption

itoggle caption Paul Sakuma/AP

The FDA hasn't approved a new weight-loss drug since 1999. In the meantime, Americans' waistlines have continued to grow. M. Spencer Green/AP hide caption

itoggle caption M. Spencer Green/AP

Many hospitals are perilously close to running out of a form of methotrexate that's necessary to inject in high doses to treat certain forms of cancer. iStockphoto.com hide caption

itoggle caption iStockphoto.com

When it comes to taking up residence in your intestines, Clostridium difficile, like these, may get some help from common heartburn drugs. Janice Carr/CDC hide caption

itoggle caption Janice Carr/CDC