Serotonin syndrome might have a genetic link...
Although the thrust of this article seems to be drug - drug interactions, I wouldn't doubt a genetic predisposition. Enter serotonin syndrome and (CYP2D6 or cytochrome P450) into PubMed's query box. A lot of school shootings, maybe most, were done by kids on SSRIs. If their defense was up to snuf, they would be tested for this genetic variation for trial, appeal or parole board.
The case of Libby Zion was straightforward. She did not tell the attending physician she had been taking drugs. As Dr. House would say...the first rule of medicine is that the patient always lies.
Libby's father had the power of the press behind him and that's the only reason it became a huge story. He did not want to face the fact his daughter was not the perfect little girl he thought she was. And that's the truth.