TABLE 1. Number and percentage of opioid overdose deaths that co-involved another opioid, by opioid type (illicitly manufactured fentanyl [IMF],* fentanyl analogs,^† heroin, and prescription opioids^§) — 25 states,^¶ State Unintentional Drug Overdose Reporting System (SUDORS), January–June 2018.

Opioid type involved in opioid death**	No. of deaths Jan–Jun 2018	No. of deaths with co-involved opioid types (%)
		IMF	Fentanyl analog	Heroin	Other illicit opioid††	Prescription opioid
Any suspected IMF	9,105	—	2,199 (24.2)	3,589 (39.4)	4,785 (52.6)	1,250 (13.7)
Any fentanyl analog	2,678	2,199 (82.1)	—	1,172 (43.8)	2,366 (88.3)	356 (13.3)
Any suspected heroin	5,281	3,589 (68.0)	1,172 (22.2)	—	3,747 (71.0)	796 (15.1)
Any prescription opioid	3,853	1,250 (32.4)	356 (9.2)	796 (20.7)	1,562 (40.5)	—

*Among fentanyl-involved deaths, 87.2%, 11.2%, and 1.6% were suspected to involve IMF, had insufficient data to classify the fentanyl death as IMF or prescription fentanyl, and were suspected to involve prescription fentanyl, respectively. Because the majority of identified cases involved IMF, and characteristics of unclassified fentanyl deaths were more similar to IMF-involved deaths than to prescription fentanyl–involved deaths, unclassified fentanyl deaths were categorized as suspected IMF-involved.

^† Fentanyl analog-involved deaths included deaths involving carfentanil, acetylfentanyl, acrylfentanyl, furanylfentanyl, 3-methylfentanyl, butyrylfentanyl, cyclopropylfentanyl, crotonylfentanyl, 4/para-fluorofentanyl, 4/para-fluorobutyrylfentanyl, 4/para-isobutyrylfentanyl, cyclopentylfentanyl, methoxyacetylfentanyl, isobutyrylfentanyl, furanylethylfentanyl, methoxybutyrlfentanyl, benzylfentanyl, valerylfentanyl, alpha-methylfentanyl, tetrahydrofuranylfentanyl, ocfentanil, betahydroxythiofentanyl, alfentanil, sufentanil, methylcarfentanil, methylthiofentanyl, phenylfentanyl, omethylacetylfentanyl, and isovalerylfentanyl.

^§ Included any opioid deaths involving prescription opioids (oxycodone, oxymorphone, hydrocodone, hydromorphone, tramadol, buprenorphine, methadone, morphine, codeine, prescription fentanyl, meperidine, tapentadol, dextrorphan, levorphanol, propoxyphene, noscapine, and pentazocine). Other drugs might have been involved or co-occurred with the prescription opioid.

^¶ Alaska, Connecticut, Delaware, Florida, Georgia, Illinois, Kentucky, Maine, Massachusetts, Minnesota, Missouri, Nevada, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Utah, Vermont, Virginia, Washington, and Wisconsin.

** U-series deaths were not reported in the analyses because only 63 deaths involved U-series drugs in the 25 SUDORS states during January–June 2018.

^†† Any illicit opioid other than that listed in drug category. For deaths involving illicit opioids (IMF, fentanyl analogs, and heroin) the illicit drug is excluded from this column. For example, 52.6% of IMF deaths co-involved at least one fentanyl analog, heroin, or U-series drug.