Once diagnosed with osteoporosis, patients have a number of treatment options. In addition to calcium and Vitamin D, doctors often prescribe bisphosphonate drugs to treat osteoporosis. Bisphosphonates are a class of drugs used to strengthen bones and inhibit bone breakdown. There are currently four on the market which are FDA approved to treat osteoporosis:
- alendronate (Fosamax)
- risedronate (Actonel)
- ibandronate (Boniva)
- zoledronic acid (Reclast)
The first three are pills (taken once a week or once a month) and the last is an intravenous medication given once a year.
Dr. Streeten says that one injection of zoledronic acid per year is approximately as good at preventing fractures as a year of an oral medication, such as Fosamax. “The disadvantage of the IV is that it may cause flu like symptoms one day after the infusion,” she says.
In one study, an increased risk of an irregular heart rhythm, atrial fibrillation, was seen””in 1.5 percent of people who had IV zoledronic acid compared to 0.5 percent in those who did not receive the drug. Another similar study showed no increased risk of atrial fibrillation.
“It appears to be a very small risk,” Streeten says. “IV zoledronic acid can also reduce the level of blood calcium transiently, but that's not a problem if the person is getting the recommended amount of calcium and Vitamin D.”
“Data show that all four drugs reduce the risk of spine fracture by half. Alendronate, risedronate and zoledronic acid but not ibandronate also reduce the risk of hip fracture,” says Streeten.
There are a couple of other FDA-approved drugs to treat osteoporosis, but studies show that they are less effective than bisphosphonates in reducing the risk of fracture. One is a nasal spray called calcitonin (Miacalcin), which reduces the risk of spine fractures by a third but does not reduce hip fracture risk. Raloxifene (Evista) is another drug used for the prevention and treatment of osteoporosis. Raloxifene, which is similar to the breast cancer drug tamoxifen, has an estrogen-like effect on the bones. Raloxifene, like calcitonin, reduces spine fracture risk by a third but does not reduce hip fracture risk.
Other drugs are currently being studied for treating osteoporosis including strontium and denosumab, but are not yet FDA approved for use or available in the United States.
UMMC experts can help prescribe the right medicine based on your individual situation.
To make an appointment with Dr. Streeten at the Metabolic Bone Diseases Clinic, please call 410-328-5196, 410-328-6219, or toll-free at 1-800-492-5538.