epidemiology for Poisoning and Drug Overdosage

About 5 million poison exposures occur in the United States each year. Most are acute, accidental (unintentional), involve a single agent, occur in the home, result in minor or no toxicity, and involve children under 6 years of age. Pharmaceuticals are involved in 47% of exposures and 84% of serious or fatal poisonings. Unintentional exposures can result from the improper use of chemicals at work or play; product mislabeling; label misreading; mistaken identification of unlabeled chemicals; uninformed self-medication; and dosing errors by nurses, parents, pharmacists, physicians, and the elderly. Excluding the recreational use of ethanol, attempted suicide (deliberate self-harm) is the most common reason for intentional exposure. Unintended poisonings may result from the recreational use of prescribed and over-the-counter drugs for psychotropic or euphoric effects (abuse) or excessive self-dosing (misuse).

About 25% of exposures require health professional evaluation, and 5% of all exposures require hospitalization. Poisonings account for 5–10% of all ambulance transports, emergency department visits, and intensive care unit admissions. Up to 30% of psychiatric admissions are prompted by attempted suicide via overdosage. Overall, the mortality rate is low: 0.4% of all exposures. It is much higher (1–2%) in hospitalized patients with intentional (suicidal) overdose, who account for the majority of serious poisonings. Acetaminophen is the pharmaceutical agent most often implicated in fatal poisoning. Overall, carbon monoxide is the leading cause of death from poisoning, but this is not reflected in hospital or poison center statistics because patients with such poisoning are typically dead when discovered and are referred directly to medical examiners.