5 common medications that can have serious side effects

Report new symptoms immediately if you take one of these.

Taking blood thinners and prescription painkillers such as opioids can have potentially life-threatening complications. But many medications — even over-the-counter drugs — have the potential for dangerous side effects. "In most cases, the risk of serious side effects is very rare — much less than 1% of the time," says Dr. Joshua Gagne, a pharmacist and epidemiologist with Harvard-affiliated Brigham and Women's Hospital.

If you're taking any of the following drugs, learn the rare risks.