One of the best known of these cases is the experience of Philadelphia fiction writer Diane Ayres, who in 1992 took a single Floxin tablet that her physician prescribed for a minor urinary tract infection and wound up delirious in the emergency room six hours later. She is now diagnosed with manic-depressive illness triggered by the powerful antibiotic, for which she has been treated with medication for nine years, says her husband, investigative journalist Stephen Fried. Fried chronicled his wife's struggle as "friendly fire in the war on disease" in the 1998 book "Bitter Pill: Inside the Hazardous World of Legal Drugs."