Pharmacokinetic profile and behavioral effects of gabapentin in the horse.
J Vet Pharmacol Ther
; 33(5): 485-94, 2010 Oct.
Article
em En
| MEDLINE
| ID: mdl-20840393
ABSTRACT
Gabapentin is being used in horses although its pharmacokinetic (PK) profile, pharmacodynamic (PD) effects and safety in the equine are not fully investigated. Therefore, we characterized PKs and cardiovascular and behavioral effects of gabapentin in horses. Gabapentin (20 mg/kg) was administered i.v. or p.o. to six horses using a randomized crossover design. Plasma gabapentin concentrations were measured in samples collected 0-48 h postadministration employing liquid chromatography-tandem mass spectrometry. Blood pressures, ECG, and sedation scores were recorded before and for 12 h after gabapentin dosage. Nineteen quantitative measures of behaviors were evaluated. After i.v. gabapentin, the decline in plasma drug concentration over time was best described by a 3-compartment mammillary model. Terminal elimination half-life (t(1/2γ) ) was 8.5 (7.1-13.3) h. After p.o. gabapentin terminal elimination half-life () was 7.7 (6.7-11.9) h. The mean oral bioavailability of gabapentin (± SD) was 16.2 ± 2.8% indicating relatively poor absorption of gabapentin following oral administration in horses. Gabapentin caused a significant increase in sedation scores for 1 h after i.v. dose only (P < 0.05). Among behaviors, drinking frequency was greater and standing rest duration was lower with i.v. gabapentin (P < 0.05). Horses tolerated both i.v. and p.o. gabapentin doses well. There were no significant differences in and . Oral administration yielded much lower plasma concentrations because of low bioavailability.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Ansiolíticos
/
Sedação Consciente
/
Ácidos Cicloexanocarboxílicos
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Ácido gama-Aminobutírico
/
Aminas
/
Cavalos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Vet Pharmacol Ther
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos