Open AccessBioavailability of butorphanol after intranasal administration to horses
Author(s) -
Vı́tor F. Ferreira,
María Inés Velloso,
M. F. Landoni
Publication year - 2020
Publication title -
bulgarian journal of veterinary medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.211
H-Index - 10
eISSN - 1311-1477
pISSN - 1313-3543
DOI - 10.15547/bjvm.2019-0051
Subject(s) - butorphanol , bioavailability , nasal administration , pharmacokinetics , crossover study , volunteer , medicine , volume of distribution , pharmacology , absorption (acoustics) , anesthesia , acoustics , agronomy , biology , physics , alternative medicine , pathology , placebo
The aim of the present study was to describe butorphanol pharmacokinetics and bioavailability following intranasal administration to horses. Six adult horses received 0.05 mg/kg butorphanol, in a randomised crossover design, by either intravenous or intranasal route. Plasma concentrations of butorphanol were measured at predetermined time points using liquid chromatography/mass spectrometry assay. After intravenous injection, mean ±SD butorphanol steady-state volume of distribution and clearance was 3.20 ± 1.77 l/kg and 3.18 ± 1.47 L/kg/h, respectively. Terminal half-lives for butorphanol after intravenous and intranasal administrations were 0.68 ± 0.17 h and 1.79 ± 1.43 h. For intranasal administration, absorption half-life and peak plasma concentration were 0.43 ± 0.33 h and 1.95 ± 1.7 ng/mL, respectively. Bioavailability was 54.45 ± 20.09%. Intranasal butorphanol administration in horses is practical, not stressful and well tolerated. Therefore, it might be a substitute to the intravenous route in adult horses