U-47700: A Clinical Review of the Literature.

BACKGROUND: U-47700 is a synthetic opioid developed by The Upjohn Company in the 1970s, which has recently appeared in the news and medical literature due to its toxicity. Currently, there are no clinical trial data assessing the safety of U-47700. OBJECTIVE: To describe the signs and symptoms of ingestion, laboratory testing, and treatment modalities for U-47700 intoxication. DISCUSSION: We searched PubMed, Embase, Web of Science, and EBSCO for articles using the term "U-47700" and "47700." The following inclusion criteria were used: had to be in English; full text; must involve humans; must be either a randomized control trial, prospective trial, retrospective analysis, case series, or case report; and must include clinical findings at presentation. We identified and extracted data from relevant articles. Ten relevant articles were included with 16 patients. Patients that died after overdose with U-47700 typically presented to the hospital with pulmonary edema. Patients who survived an overdose presented with decreased mental status and decreased respiratory rate suggestive of an opioid toxidrome. Patients also commonly had tachycardia. Immunoassays failed to identify U-47700, and the identification of U-47700 required the use of chromatographic and spectral techniques. CONCLUSION: We report the first clinical review of U-47700 intoxication.