5 common medications that can have serious side effects

Report new symptoms immediately if you take one of these.

Published: January, 2020

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.

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