Dear Dr. Roach: Would you please discuss the use of Evista for treatment of osteoporosis as an alternative to bisphosphonates? Which medication to take is confusing, since they all have serious side effects.
Dear S.K.: Raloxifene (Evista) has some properties similar to estrogen and some properties opposite to it. It acts like estrogen in bones, increasing bone density and reducing fracture risk, and it acts as an anti-estrogen in normal breast tissue and breast cancer, reducing the risk of developing breast cancer. Raloxifene is not as effective as bisphosphonates (such as alendronate), so normally it is used in women who can’t or shouldn’t take bisphosphonates, or in women who have an increased risk for breast cancer and osteoporotic fractures.
You are right that all medications have potential for side effects. For raloxifene, the most concerning is a risk for blood clots, similar to that of estrogen, with a higher risk for about 1 in 1,000 women taking the medication for a year. This needs to be balanced against the benefits of one fewer case of vertebral fractures and also one fewer case of invasive breast cancer per thousand women per year. A particular woman at very high risk for breast cancer or fracture would be expected to have more benefit, but those at higher risk for blood clots would likely have a higher increase in risk.
Not all women need medication osteoporosis treatment, and I get many letters from women who aren’t appropriate candidates for medication, but are still prescribed drugs with significant side-effect risks. Medication treatment should be only for women at high risk for fracture, based on a very low bone mineral density, previous fracture or high risk of fracture based on their FRAX score (shef.ac.uk/FRAX/).
It’s always important to weigh the risks of a medication against the risks of not taking it.
Email questions to ToYourGoodHealth@ med.cornell.edu.