"Of the approximately 2.5 million drug misuse or abuse ED visits that occurred during 2011, a total of 1,252,500, or just over half (50.9%), involved illicit drugs (Table 4). A majority (56.3%) of illicit drug ED visits involved multiple drugs. Overall, 27.9 percent of visits involving illicit drugs also involved alcohol.
"Cocaine and marijuana were the most commonly involved drugs, with 505,224 ED visits (40.3%) and 455,668 ED visits (36.4%), respectively. Cocaine and marijuana were followed by heroin, at 258,482 ED visits, or 20.6 percent, and then by amphetamines/methamphetamine, at 159,840 visits, or 12.8 percent."

Note: According to the DAWN report, "DAWN captures drugs that are explicitly named in the medical record as being involved in the ED visit. The relationship between the ED visit and the drug use need not be causal. That is, an implicated drug may or may not have directly caused the condition generating the ED visit; the ED staff simply named it as being involved." (p. 15)

Source

Substance Abuse and Mental Health Services Administration, Drug Abuse Warning Network, 2011: National Estimates of Drug-Related Emergency Department Visits. HHS Publication No. (SMA) 13-4760, DAWN Series D-39. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2013, p. 25 and p. 15.
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