Women taking some common drugs, including tamoxifen and raloxifene, were 38 percent less likely to develop the most common type of breast cancer than those given a placebo, according to a new study in the journal Lancet.
The reduced risk extended at least five years after stopping treatment.
According to drugs.com, tamoxifen blocks the actions of estrogen and is often used to treat some types of breast cancer. A common brand name for the drug is Soltamox.
Raloxifene is used to help treat and prevent osteoporosis only in postmenopausal women, according to the Mayo Clinic.
Both are prescription drugs.
Some women are hesitant to take the drugs because of possible side effects
including a greater risk of developing blood clots and endometrial cancer.