When the color of a pill changes between prescriptions, people are less likely to take their medications. A new study shows patients may be unsure about their medications and stop taking them. The color of pills can often change when switching from a brand-name to a generic drug. The researchers found a slight difference in the percentage of people who filled their orders on time and those who did not when a color change was taken into account. The research is published in "JAMA Internal Medicine."