Have you ever taken phenylephrine for a stuffed-up nose and then felt better? If so, you might have been perplexed when Food and Drug Administration experts said last year that that the drug — which is in some versions of DayQuil, Sudafed, and other medicines — is no more effective than a placebo. On this episode of the “First Opinion Podcast,” we talk with professor and researcher Michael Bernstein about the placebo effect and its counterpart, the “nocebo effect” — if you tell patients something will make them feel worse, it generally comes true.