Every year, pharmaceutical industry sales representatives drop off to my office zillions of beautifully colored samples of cold nostrums during the respiratory disease season. I pass them out, at least to patients who can't be persuaded not to use them. But—and I'm sure the sales reps will not be pleased to hear this—I always tell parents that the only reason I'm giving them this junk is so they can find out for themselves how worthless it is.