Osteonecrosis of the Jaw Caused by Bisphosphonates

Content provided by the Faculty of the Harvard Medical School

Osteonecrosis of the Jaw Caused by Bisphosphonates

Question:

I know that a rare side effect of taking Fosamax is necrosis of the jawbone. If this happens, does the damaged jaw improve after stopping the Fosamax or is the damage permanent?

Answer:

Osteonecrosis of the jaw is a rare complication of using bisphosphonates. These drugs treat the bone-thinning disease osteoporosis. They include alendronate (Fosamax), risedronate (Actonel), ibandronate (Boniva), and zoledronic acid (Zometa or Reclast).

More than 90% of cases have occurred among cancer patients receiving intravenous medications, especially zoledronic acid. The risk for people taking oral bisphosphonates appears to be quite low. In studies of more than 17,000 patients taking the drug for up to 10 years, no cases of osteonecrosis of the jaw were reported.

When osteonecrosis of the jaw develops, the blood supply of the bone in the jaw is interrupted and the bone dies. Pain, tooth loss, and the appearance of exposed bone are common symptoms. Infection occasionally complicates this condition. Most of the time, osteonecrosis of the jaw heals well, although limited surgery and antibiotics may be needed. In a recent study of 97 cancer patients, 75% of cases of osteonecrosis of the jaw healed over time.

Limited debridement (removal of dead bone) is sometimes recommended to smooth sharp bone edges. A mouth guard (or other dental appliance) may be helpful to protect the area while it heals.

If you are considering Fosamax treatment, it's probably a good idea to have a complete dental exam first. If you need dental work, have it done before starting Fosamax. This recommendation is based on the observation that many cases of drug-related osteonecrosis of the jaw occur soon after having a tooth removed or having dental surgery.

Reports of osteonecrosis of the jaw with Fosamax treatment are clearly concerning. But it's likely that for most people with osteoporosis, the benefits of treatment outweigh the risks.

Robert Shmerling, M.D., is associate physician and clinical chief of rheumatology at Beth Israel Deaconess Medical Center and an associate professor in medicine at Harvard Medical School. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program and has been a practicing rheumatologist for over 25 years.

Last updated:	July 20, 2009