- With Mayo Clinic endocrinologist
Kurt A. Kennel, M.D.
Risk factors (1)
- High-protein diets: Are they safe?
Treatments and drugs (3)
- Osteoporosis medications: Must they be taken indefinitely?
- Osteoporosis and long-term prednisone: What is the risk?
- Fosamax and bisphosphonate-associated osteonecrosis: What's the risk?
Question
Fosamax and bisphosphonate-associated osteonecrosis: What's the risk?
Is Fosamax a safe medication? I'm concerned about taking it because of its possible link to osteonecrosis.
Answer
from Kurt A. Kennel, M.D.
Yes, alendronate (Fosamax) is safe for the majority of people who take it. But it may pose a risk of a rare jaw disorder (osteonecrosis of the jaw) in certain people. The cause of this isn't clear.
Fosamax belongs to a class of drugs called bisphosphonates, which are used to treat and prevent osteoporosis. Some bisphosphonates are taken orally, and others are taken intravenously. This class of drugs is also used to treat some cancers involving the bone.
Since 2003, there have been reports of a possible link between bisphosphonates and a rare disorder called osteonecrosis, or "death of bone," involving the jaw — a condition marked by pain, swelling, infection and exposed bone. The majority of cases of osteonecrosis of the jaw involved people with cancer who were receiving chemotherapy and had been given intravenous bisphosphonates to treat cancer that had spread (metastasized) to the bone.
However, a small number of cases of osteonecrosis of the jaw have been reported in people taking oral bisphosphonates — such as Fosamax — for osteoporosis. These have been primarily associated with active dental disease or a recent dental procedure, such as a tooth extraction.
Osteonecrosis of the jaw is a serious disorder. But so is osteoporosis. If you take a bisphosphonate for osteoporosis, don't stop taking the medication without consulting your doctor.
Keep in mind that the risk of developing osteonecrosis of the jaw due to bisphosphonate use is very low in people without cancer or dental problems. If your doctor recommends a bisphosphonate for osteoporosis, consider getting any needed dental work done before starting this medication. If you currently take an oral bisphosphonate and need a dental procedure, you should discuss this with your doctor and dentist.
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- Silverman SL, et al. Osteonecrosis of the jaw and the role of bisphosphonates: A critical review. The American Journal of Medicine. 2009;122:S33.
- Ruggiero SL, et al. American Association of Oral and Maxillofacial Surgeons position paper on bisphosphonate-related osteonecrosis of the jaws — 2009 update. Journal of Oral and Maxillofacial Surgery. 2009;67(suppl):2.
- Assael LA. Oral bisphosphonates as a cause of bisphosphonate-related osteonecrosis of the jaws: Clinical findings, assessment of risks, and preventive strategies.

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