Millions of people who take Fosamax to strengthen bones weakened by osteoporosis should not panic about a report linking the popular drug to esophageal cancer, says UNC's Dr. Nicholas Shaheen.

A recent FDA study showed that 23 people who had taken Fosamax between October 1995 and May 2008 developed esophageal cancer, which affects the tissues lining the esophagus, the muscular tube through which food passes from the throat to the stomach.

Shaheen, the director of UNC Health Care's Center for Esophageal Diseases, questions the conclusiveness of the study. He maintains the popularity of the drug makes it that much more difficult to determine a link.

"If you take drug "Z," which is incredibly popular, and then you take a disease, you wouldn't be too surprised if some people got the disease while on that drug," he said. "With such a small number of cases, I don't think it's really something to get too excited about, especially when we're only talking about 13 years."

Shaheen says bisphosphonates, the class of drugs that includes Fosamax and others like Boniva, have been shown to cause irritation in the esophagus when there is already narrowing caused by inflammation or disease.

"If the bisphosphonate gets hung up above the narrowing, it can irritate or burn the tissue around where it gets hung up," he said. "That's because the pill never went down into the stomach where it is very well tolerated."

Shaheen recommends that patients with severe reflux disease or a pre-cancerous condition called Barrett's Esophagus talk with their doctor if they have concerns, but he cautions against physicians rushing to prescribe alternate drugs or patients taking themselves off Fosamax altogether.

"At this point, I personally am not going to change anybody's medicine until we get a better idea if there really is a risk," he said. "The value of these bone medicines is substantial, and it may be that this is a risk worth taking."

 Hear more from Dr. Shaheen by clicking on the video link above. 

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