Boniva is a drug in the class known as bisphosphonates and was developed for the treatment of osteoporosis. It is much like the earlier drugs, Fosamax and Actonel (which can be taken daily or weekly), but its big selling point is that you can take it only once a month. All three of these drugs work by slowing or stopping the activity of osteoclasts, cells that are involved in breaking down bone. Throughout life, bone is constantly being built up and torn down, but after age 30, the amount lost exceeds the amount gained so that bones slowly become less dense. In women, this process accelerates after menopause and can lead, over time, to osteoporosis and, of greatest concern, hip and vertebral fractures.
The side effects of Boniva are similar to those of Fosamax and Actonel – digestive problems including upset stomach, heartburn, difficulty or painful swallowing, diarrhea, headache, and muscle or joint pain. Some people on bisphosphanate drugs have developed severe degeneration (osteonecrosis) of the jawbone. We are just now learning about the possibility of this disastrous side effect and don’t know how frequent it is.
(Evista, another drug used to treat osteoporosis, is not a bisphosphonate but is a selective estrogen receptor modifier, or SERM, an agent that seems to provide the benefits of estrogen replacement without increasing breast cancer risk. Side effects include hot flashes and vaginal discharge, dryness, or itching.)
I recently discussed Boniva with Victoria Maizes, M.D., executive director of the Arizona Center for Integrative Medicine here at the University of Arizona. Dr. Maizes noted that the absolute risk reduction for fractures among patients who have taken Boniva for three years is only five percent (the manufacturers will point to another figure, the "relative risk" reduction of 50 percent – which sounds good but doesn’t actually mean that 50 percent of patients who take the drug will avoid fractures. Instead, it means that Boniva reduces the small number of patients who would get fractures without treatment by 50 percent. Always look for the “absolute risk” reduction when evaluating any type of medical treatment).
Medication isn’t your only option for strengthening your bones. If you smoke, stop. Weight-bearing and strength-training exercises can help maintain bone mass, and I also recommend taking 500 to 700 mg of calcium citrate in two divided doses with meals, for a total daily intake of 1,000-1,200 mg from all sources, plus 2,000 IU vitamin D daily to promote calcium absorption. Cut back on your caffeine intake and soda consumption, and avoid excessive protein in your diet, all of which can promote calcium loss.
Andrew Weil, M.D.