North America is in the midst of its most serious drug-overdose crisis in history. From 1999 through 2015, drug-overdose deaths approximately tripled in the United States, and the majority of such deaths now involve an opioid. In 2016 alone, there were 64,000 drug-overdose deaths in the United States — more than the total number of U.S. military deaths during the Vietnam War. As a result, and despite gains in other areas of medicine and public health, the United States recently experienced its first major decline in life expectancy since 1993.