Many of the most frequently prescribed oral medications in the U.S. contain at least one ingredient that could cause an adverse reaction, new research shows. The study, reported in Science Translational Medicine, looked at more than 42,000 oral medications and identified more than three dozen inactive ingredients that have been described in medical literature to cause allergic symptoms following oral exposure. These ingredients—including lactose, peanut oil, gluten, and chemical dyes—are added to improve the taste, shelf-life, absorption, and other characteristics of a medication.
