A 22-year-old woman is brought in by members of her family, who say that she has been paranoid and uncharacteristically withdrawn during the last two weeks. Additionally, she has not been taking good care of herself. She is also having trouble sleeping and her appetite is diminished. Close questioning reveals that she “hears voices” talking about her, even when no one is physically present. She is also worried that her family may poison her. There is no history of seizures or neurological symptoms. She was in good health prior to this and is not on any medications. There is no history of illicit drug use and her family history is unremarkable. A complete blood count, serum electrolytes, random plasma glucose, renal profile, liver profile, drug screen, and CT scan of the brain are all normal.