title: A preliminary study of intranasal epinephrine administration as a potential route for anaphylaxis treatment.
abstract: BACKGROUND
  The intranasal (IN) administration of epinephrine could be an alternative route for anaphylaxis treatment. Although IN epinephrine absorption has been demonstrated in animals, such data in humans are still lacking.
  
  
  OBJECTIVE
  To study the pharmacokinetics of IN epinephrine absorption in humans.
  
  
  METHODS
  Each healthy adult (n = 5) was administered IN saline, IN epinephrine at various doses (i.e., 0.3, 0.6, 1.25, 2.5 and 5 mg), and intramuscular (IM) epinephrine at 0.3 mg. Plasma epinephrine levels at baseline and various time points up to 120 minutes after administration were determined using high-performance liquid chromatography with electrochemical detection.
  
  
  RESULTS
  Significant systemic absorption of epinephrine via IN route was observed only at the dose of 5 mg, and the absorption thereof was comparable to that of IM epinephrine; the average area-under-curve (AUC) values at 0-120 minutes for IN saline, IM epinephrine, and 5 mg IN epinephrine were 0.3, 18.3, and 19.4 ng.min/mL, respectively. In addition, the peak epinephrine concentrations and the time to reach them were also not significantly different between IM and 5-mg IN epinephrine; the corresponding values (mean ± SD) were 309 ± 88 pg/mL and 67 ± 43 min for IM epinephrine, and 386 ± 152 pg/mL and 70 ± 17 min for 5 mg IN epinephrine.
  
  
  CONCLUSIONS
  This preliminary study showed that epinephrine can be significantly absorbed via the IN route in humans. However, it requires a higher IN dose (5 mg) than the usual IM dose (0.3 mg) to achieve comparable systemic epinephrine absorption.
authors.affiliation: Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Chatchawan
authors.initials: C
authors.lastname: Srisawat
authors.forename: Kanittha
authors.initials: K
authors.lastname: Nakponetong
authors.forename: Patchanee
authors.initials: P
authors.lastname: Benjasupattananun
authors.forename: Chanthana
authors.initials: C
authors.lastname: Suratannon
authors.forename: Leatchai
authors.initials: L
authors.lastname: Wachirutmanggur
authors.forename: Siribangon
authors.initials: S
authors.lastname: Boonchoo
authors.forename: Duangjai
authors.initials: D
authors.lastname: Pankaew
authors.forename: Apirom
authors.initials: A
authors.lastname: Laocharoenkiat
authors.forename: Punchama
authors.initials: P
authors.lastname: Pacharn
authors.forename: Orathai
authors.initials: O
authors.lastname: Jirapongsananuruk
authors.forename: Nualanong
authors.initials: N
authors.lastname: Visitsunthorn
authors.forename: Pakit
authors.initials: P
authors.lastname: Vichyanond
mesh_terms: D000281:Administration, Intranasal; D000328:Adult; D000707:Anaphylaxis / Q000188:drug therapy*; D004837:Epinephrine / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male
chemical_list: D004837:Epinephrine