title: Supraventricular tachycardia and acute confusion following ingestion of e-cigarette fluid containing AB-FUBINACA and ADB-FUBINACA: a case report with quantitative analysis of serum drug concentrations.
abstract: BACKGROUND
  AB-FUBINACA and ADB-FUBINACA are structurally similar synthetic cannabinoids with potent CB1receptor agonistic effects. Very little is known about their pharmacology and toxicology.
  
  
  OBJECTIVE
  To report a case of supraventricular tachycardia and acute confusion after ingestion of e-cigarette fluid containing AB-FUBINACA and ADB-FUBINACA, with quantitative analysis of the serum drug concentrations.
  
  
  METHODS
  A healthy 24-year-old man ingested two drops of e-cigarette fluid which were later found to contain AB-FUBINACA and ADB-FUBINACA. Within 30 min of ingestion, he became somnolent, confused, and agitated, with palpitation and vomiting. On arrival to the emergency department, a short run of supraventricular tachycardia was noted, which resolved spontaneously. Bedside urine immunoassay failed to detect recreational drugs. Laboratory blood tests showed mild hypokalemia. Exposure to AB-FUBINACA and ADB-FUBINACA was confirmed analytically, with serum concentrations of 5.6 ng/mL and 15.6 ng/mL, respectively, in the blood sample collected on presentation. The patient recovered uneventfully with supportive treatment and was discharged 22 h after admission.
  
  
  CONCLUSIONS
  AB-FUBINACA and ADB-FUBINACA are orally bioavailable with rapid onset of toxicity after ingestion. In this case, supraventricular tachycardia was likely the result of exposure to AB-FUBINACA and ADB-FUBINACA. The serum concentrations of AB-FUBINACA and ADB-FUBINACA were higher than those previously reported in fatal cases.
  
  
  CONCLUSIONS
  In the context of acute poisoning, the presence of unexplained tachyarrhythmias, confusion, and a negative recreational drug screen should prompt clinicians to consider synthetic cannabinoid toxicity as a differential diagnosis.
authors.affiliation: a Emergency Medicine Unit, Li Ka Shing Faculty of Medicine , The University of Hong Kong , Hong Kong Special Administrative Region , China.
authors.forename: Rex Pui Kin
authors.initials: RPK
authors.lastname: Lam
authors.affiliation: b Hospital Authority Toxicology Reference Laboratory , Princess Margaret Hospital, Lai Chi Kok , Hong Kong Special Administrative Region , China.
authors.forename: Magdalene Huen Yin
authors.initials: MHY
authors.lastname: Tang
authors.affiliation: c Accident and Emergency Department , Queen Mary Hospital , Hong Kong Special Administrative Region , China.
authors.forename: Siu Chung
authors.identifier: http://orcid.org/0000-0003-0169-9899
authors.initials: SC
authors.lastname: Leung
authors.affiliation: b Hospital Authority Toxicology Reference Laboratory , Princess Margaret Hospital, Lai Chi Kok , Hong Kong Special Administrative Region , China.
authors.forename: Yeow Kuan
authors.initials: YK
authors.lastname: Chong
authors.affiliation: c Accident and Emergency Department , Queen Mary Hospital , Hong Kong Special Administrative Region , China.
authors.forename: Matthew Sik Hon
authors.initials: MSH
authors.lastname: Tsui
authors.affiliation: b Hospital Authority Toxicology Reference Laboratory , Princess Margaret Hospital, Lai Chi Kok , Hong Kong Special Administrative Region , China.
authors.forename: Tony Wing Lai
authors.initials: TWL
authors.lastname: Mak
mesh_terms: D003221:Confusion / Q000139:chemically induced* / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D003937:Diagnosis, Differential; D062787:Drug Overdose / Q000097:blood / Q000175:diagnosis; D066300:Electronic Nicotine Delivery Systems / Q000009:adverse effects*; D006801:Humans; D007191:Indazoles / Q000097:blood / Q000506:poisoning*; D008297:Male; D011237:Predictive Value of Tests; D015813:Substance Abuse Detection; D019966:Substance-Related Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D013617:Tachycardia, Supraventricular / Q000139:chemically induced* / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007191:Indazoles; C000613078:ADB-FUBINACA; C000615602:AB-FUBINACA
keywords: Synthetic cannabinoids; cardiac arrhythmias; designer drug; novel psychoactive substances; toxicity