Watch for this common reaction to niacin

"This is one of my favorite problems to 'diagnose,'" says Joan Somes, PhD, MSN, RN, CEN, FAEN, ED educator at St. Joseph's Hospital in St. Paul, MN.

After taking over-the-counter niacin for cholesterol, patients present to the ED with significant flushing. "Their skin feels tingling, and they are sure they are in the process of dying," she says. "Some will actually vasodilate enough they can drop their blood pressure. But typically, the reaction to this drug is uncomfortable, but benign."

Ask about supplements, vitamins, and over-the-counter drugs, says Somes. "I would say I see this in our ED on the average of once every couple of months," she says. "In fact, one of our docs recently had it happen to him, and he came to the ED, just in case."