How serious are the risks of bisphosphonates, such as alendronate (Fosamax) and risedronate (Actonel), when taken for osteoporosis? Can they actually cause additional bone problems?
Answers from Kurt A. Kennel, M.D.
Like all drugs, bisphosphonates have risks as well as benefits. For well over a decade, though, doctors have prescribed bisphosphonates to millions of people, very few of whom developed major side effects.
Still, reports of an association between bisphosphonate use and two rare but serious problems — osteonecrosis of the jaw and a specific type of fracture in the long bone of the leg (femur) — have raised concerns. Osteonecrosis of the jaw develops when the jaw bone fails to heal after a minor injury — for example, the type of injury sometimes caused by getting a tooth pulled.
A clear cause-and-effect relationship between bisphosphonate use and jaw osteonecrosis remains unproved. The best estimate of risk is 0.1 percent, meaning the condition occurs in 1 out of every 1,000 women taking bisphosphonates over the course of a year. The risk of a bisphosphonate-related leg fracture seems to be much lower than that of jaw osteonecrosis.
Overall, bisphosphonates are more likely to help you by preventing fractures than to hurt you by causing jaw problems or unusual femur fractures. This is particularly true for women with postmenopausal osteoporosis.
Nov. 08, 2012
Kurt A. Kennel, M.D.
See more Expert Answers
- Khosla S, et al. Benefits and risks of bisphosphonate therapy for osteoporosis. Journal of Endocrinology and Metabolism. 2012;97:2272.
- Haworth A, et al. Skeletal complications of bisphosphonate use: what the radiologist should know. The British Journal of Radiology. 2012; 85:1333.
- 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(supp1):2-12.
- Schilcher J, et al. Bisphosphonate use and atypical fractures of the femoral shaft. New England Journal of Medicine. 2011;364:1728.
- AskMayoExpert. What is the risk of jaw osteonecrosis with the use of bisphosphonates for treatment of osteoporosis? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2012.
- Hellstein JW, et al. Managing the care of patients receiving antiresorptive therapy for prevention and treatment of osteoporosis: Executive summary of recommendations from the American Dental Association Council on Scientific Affairs. Journal of the American Dental Association. 2011;142:1243.
- AskMayoExpert. Do bisphosphonates cause unusual fractures in patients with osteoporosis? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2012.