"Opioid overdose, a major source of morbidity and mortality worldwide, accounts for half of the mortality among heroin users (1) and is a leading cause of death among adults in the United States (2). Naloxone is a safe, effective, short-acting opioid antagonist for intravenous, intramuscular, subcutaneous, or intranasal administration by medical personnel and—since the late 1990s—laypersons to reverse opioid overdose. (3). Naloxone distribution is endorsed by the American Medical Association, generally integrated into preexisting services, and targeted at anyone at risk for witnessing or having an opioid overdose. Naloxone “kits” are usually wallet-sized packets containing 2 doses of naloxone and other items, including syringes, brochures, simple rescue breathing masks, and brief educational materials about overdose risks and management. As of 2010, a total of 188 U.S. programs distributing naloxone reported training 53,032 persons and recording 10,171 reversals (3)."
Coffin, Phillip O., MD, and Sullivan, Sean D. PhD, "Cost-Effectiveness of Distributing Naloxone to Heroin Users for Lay Overdose Reversal," Annals of Internal Medicine 2013 Jan 1;158(1):1-9. doi: 10.7326/0003-4819-158-1-201301010-00003.