The death of Libby Zion, an 18-year-old college student, in a New York hospital on March 5, 1984, led to a highly publicized court battle and created a cause célèbre over the lack of supervision of inexperienced and overworked young doctors. But only much later did experts zero in on the preventable disorder that apparently led to Ms. Zion’s death: a form of drug poisoning called serotonin syndrome. --snip-- In its classic form, serotonin syndrome involves three categories of symptoms: ¶Cognitive-behavioral symptoms like confusion, disorientation, agitation, irritability, unresponsiveness and anxiety. --snip-- Perhaps adding to the diagnostic challenge is the fact...