Examples

Generic Name	Brand Name
alendronate	Fosamax
etidronate (not approved by FDA for osteoporosis)	Didronel
ibandronate	Boniva
risedronate	Actonel
risedronate with calcium carbonate	Actonel with Calcium
zoledronic acid	Reclast

You take most bisphosphonates by mouth-every day, once or twice a week, or even once a month. Zoledronic acid is given intravenously, usually only once each year. One form of ibandronate is also given intravenously, usually every 3 months.

Etidronate (Didronel) is not approved by the U.S. Food and Drug Administration (FDA) for osteoporosis. But it is used in Canada and Europe for this purpose.

How It Works

Bisphosphonates are antiresorptive medicines, which means they slow or stop the natural process that dissolves bone tissue, resulting in maintained or increased bone density and strength. ¹ This may prevent the development of osteoporosis. If osteoporosis already has developed, slowing the rate of bone thinning reduces the risk of broken bones.

Bisphosphonates may be taken by men or women.

Why It Is Used

Bisphosphonates are commonly used for the prevention and treatment of osteopenia and osteoporosis.

Bisphosphonates are also used to treat other bone diseases such as Paget's disease.

Bisphosphonates should not be taken by:

• Pregnant women.
• People with severe kidney problems.
• People with severe heartburn or inflammation of the esophagus (the tube that connects the throat to the stomach).

How Well It Works

Studies show that bisphosphonates increase bone thickness and lower the risk of fractures. If you take alendronate or risedronate, you may not be as likely to break a bone. ² For example, a study of postmenopausal women who took alendronate for 10 years reported increased bone density and effective prevention of fractures. This effect decreases if alendronate use is discontinued. ³

Side Effects

Side effects are uncommon if the medicine is taken as directed, but may include:

• Heartburn, abdominal pain, and irritation of the esophagus.
• Headache and pain in muscles and joints.
• Constipation, diarrhea, and increased gas (flatulence).
• Difficulty swallowing (dysphagia).
• Allergic reactions.

Serious problems with bone healing, particularly after dental surgery, have been found in some people taking bisphosphonates. ⁴ If you are taking bisphosphonates and need dental surgery, talk with your doctor.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

The long-term effects of taking bisphosphonates for many years are not known.

For the best results and to reduce the risk of irritation to your esophagus if you take bisphosphonates by mouth:

• Take bisphosphonates in the morning with a full glass of water at least 30 minutes before eating a meal, drinking a beverage, or taking any other medicine.
• Sit or stand (don't lie down) for at least 30 minutes after taking a bisphosphonate. This helps prevent heartburn.
• Do not take a bisphosphonate late in the day if you forgot to take it in the morning.

If you are taking bisphosphonates, you should also take calcium and vitamin D supplements. But calcium supplements may interfere with your body's ability to absorb bisphosphonates, so they should not be taken at the same time of day.

Bisphosphonates are sometimes taken in combination with hormone replacement therapy (HRT) by women who are not getting increased bone thickness from a bisphosphonate alone. Studies show that this combination can increase bone thickness a little more than taking either a bisphosphonate or estrogen alone. But combining medicines also leads to increased costs and increased risk of side effects. ⁵

Taking bisphosphonates at the same time as parathyroid hormone (Forteo) does not build more bone density. ⁶ But one study showed that taking parathyroid hormone for one year and then a bisphosphonate for the following year could maintain or build bone density. ⁷

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

Citations

1. American College of Obstetricians and Gynecologists (2004, reaffirmed 2008). Clinical management guidelines for obstetrician-gynecologists. Osteoporosis. ACOG Practice Bulletin No. 50. Obstetrics and Gynecology, 103(1): 203–216.

2. Hochberg MC (2002). Bisphosphonates. In SR Cummings et al., eds., Osteoporosis: An Evidence-Based Guide to Prevention and Management, pp. 181–195. Philadelphia: American College of Physicians–American Society of Internal Medicine.

3. Bone JG, et al. (2004). Ten years' experience with alendronate for osteoporosis in postmenopausal women. New England Journal of Medicine, 350(12): 1189–1199.

4. Woo S-B, et al. (2006). Systematic review: Bisphosphonates and osteonecrosis of the jaw. Annals of Internal Medicine, 144(10): 753–761.

5. Cosman F, et al. (2002). Selection of medications and guidelines for fracture prevention. In SR Cummings et al., eds., Osteoporosis: An Evidence-Based Guide to Prevention and Management, pp. 273–281. Philadelphia: American College of Physicians–American Society of Internal Medicine.

6. Black DM, et al. (2003). The effects of parathyroid hormone and alendronate alone or in combination in postmenopausal osteoporosis. New England Journal of Medicine, 349(13): 1207–1215.

7. Black DM, et al. (2005). One year of alendronate after one year of parathyroid hormone (1-84) for osteoporosis. New England Journal of Medicine, 353(6): 555–565.