Food and Drug Administration advisers voted Friday to require makers of widely used osteoporosis drugs to clarify how long patients should take them for the greatest benefit and least risk. The FDA itself will later decide what the new label wording should say for each of the drugs: Fosamax, Boniva, Actonel, Atelvia and Reclast. The agency could require wording that recommends limiting how long each drug is taken, though it's not yet clear how long that would be. A few patients have suffered serious complications, including jawbone destruction, unusual thighbone fractures and cancer of the esophagus, generally after several years taking the medicines, which include pills and longer-acting intravenous treatments.