Watch out for dangerous combinations of over-the-counter cold medicine and prescription drugs - two pharmacoepidemiology experts explain the risks 
When colds, flus and allergies hit, many people automatically turn to over-the-counter medications to push through and treat their symptoms. These include decongestants, painkillers, cough or allergy medicines and combinations thereof. Nearly 70% of adults in the U.S. use over-the-counter medications as a first-line response for treating cold and flu symptoms. Although these medications are easily accessible and widely used, it might come as a surprise to many people to learn that they are not risk-free.
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