Studies suggest the drug could raise the risk of cancer of the esophagus and a bone-killing infection in rare cases

In a letter to the New England Journal of Medicine published Jan. 1, a Food and Drug Administration official reported that since Fosamax was first marketed in 1995, 23 cases of esophageal cancer in patients taking the drug -- including eight deaths -- have been reported to the agency. And a USC study published in the January issue of the Journal of the American Dental Assn. reported that nine patients who were taking Fosamax suffered osteonecrosis of the jaw -- a bone-killing infection -- after having teeth extracted at USC dental clinics.

An estimated 30 million Americans take Fosamax or some other oral bisphosphonate: ibandronate (Boniva), risedronate (Actonel) and Reclast (zoledronic acid). These drugs have dominated the osteoporosis market based on their effectiveness at slowing bone loss, their convenience (available in pill forms) and the movement away from hormone replacement therapy. A typical patient is a postmenopausal woman with bone density T-scores of negative 2.5 or lower (the definition for osteoporosis). Men also experience bone loss with age and are prescribed oral bisphosphonates.

Learn more about Fosamax dangers and the legal rights of patients injured by Fosamax.