http://www.pharmacytimes.com/news/Most-Fatal-Poisonings-Linked-to-Prescription-Drugs
While opioid analgesics resulted in the most fatal poisonings, the street drug heroin topped the list of drugs that caused death, at 325 cases. Methadone was the leading pharmaceutical ingredient, causing 178 fatalities. Many of the methadone-related deaths involved the tablet form of the drug, as opposed to the liquid or diskette formulations, according to the study. Oxycodone, hydrocodone, acetaminophen, and morphine were the next leading causes of fatal poisoning.
Prescription opioid exposures involving children, which totaled 2591 in 2002, more than doubled in a 10-year span, numbering 5541 cases in 2012. Child deaths involving prescription analgesics increased from 1 to 7 annually in that same time period, the study reported. Methadone also led to the most pediatric deaths.