Potential drug interactions from prescribed medications are common among cancer patients and may cause unnecessary harm, according to a study in the April 18 Journal of the National Cancer Institute. Cancer patients often take several medications at the same time, not only for treating their cancer but also for side effects and other secondary illnesses. Because of this, they can be at high risk for adverse drug interactions and duplicate medications. Consequences of these interactions can range from inactivation of cancer-fighting medications to severely injuring or killing the patient. >>> Discuss This Story