Aside from causing unbearable pain that can not be relieved by ordinary painkillers, osteonecrosis of the jaw (ONJ), can also lead to infections of the face and neck, headaches, bad breath, and difficulty eating. In severe cases, patients may have difficulty breathing or require a feeding tube to avoid malnutrition, according to the July 27, 2006, Sidney Morning Herald.
The debate over the cause of the rise in cases of ONJ picked up speed in 2003, when Dr Robert Marx, chief of oral and maxillofacial surgery at the University of Miami, wrote a paper in the Journal of Oral Maxillofacial Surgery and referred to osteonecrosis of the jaw as "a growing epidemic."
Dr Marx cited 36 patients who had received intravenous bisphosphonates, the class of drugs to which Fosamax belongs, and experienced "painful bone exposure," and "were unresponsive to surgical or medical treatments."
Since 2003, more than 3,000 published cases of ONJ have been reported, according to the July 24, 2006, Goldsboro News-Argus. While most of the cases involve cancer patients on the intravenous versions of the drug, a few years ago, ONJ began turning up in otherwise healthy women taking Fosamax to increase bone density.
Most documented cases have been in people who have had a tooth extraction, a root canal, oral surgery or some other type of mouth trauma. At present there is no effective treatment or cure for ONJ.
But the problem is that the drug deposits in the entire skeleton and surgical intervention, which may bring temporary relief, simply exposes more bone to infection and death.
And stopping Fosamax before dental work, experts say, will not lower the risk of ONJ because the drug remains in the bones for up to 10 years.
Experts say that despite the FDA warning sent to prescribing physicians in 2004, its been an uphill battle getting medical professionals to recognize the seriousness of the problem. While most dentists and oncologists are aware of the danger, doctors who commonly write the prescriptions for Fosamax seem to be far less informed because there has been virtually no decrease in the number of prescriptions written for the drug.
Until recently Fosamax was prescribed to older women with osteoporosis, a known risk factor in bone fracture. But in recent years, Merck has aggressively promoted the drug for use by much young women still in their 40s and 50s, who have minimal risk factors. And due to an intentional marketing strategy by Merck, these younger women are being advised to stay on Fosamax for the rest of their lives.
Experts warn that the risk of ONJ in younger women is actually higher than with elderly women because they are more likely to have all their teeth and the potential need for future extractions, implants, or dental surgery is higher.
Fosamax entered the US market in 1995, and within 10 years, it became Merck's second best selling drug, with world-wide sales of $3.2 billion in 2005, and over 22 million prescriptions written in the US alone, according to the drug research firm IMS Health.
It was the first oral bisphosphonate to gain FDA approved and is the biggest seller in its class. Merck's SEC filing for the second quarter of 2006, reports Fosamax sales of $821 million.