Pharmacokinetics of the injectable formulation of methadone hydrochloride administered orally in horses

R. L. Linardi; A. M. Stokes; S. A. Barker; C. Short; G. Hosgood; C. C. Natalini

doi:10.1111/j.1365-2885.2009.01071.x

Back

Pharmacokinetics of the injectable formulation of methadone hydrochloride administered orally in horses

Journal article

Peer reviewed

Pharmacokinetics of the injectable formulation of methadone hydrochloride administered orally in horses

R. L. Linardi, A. M. Stokes, S. A. Barker, C. Short, G. Hosgood and C. C. Natalini

Journal of veterinary pharmacology and therapeutics, Vol.32(5), pp.492-497

2009

DOI: https://doi.org/10.1111/j.1365-2885.2009.01071.x

PMID: 19754917

Files and links (1)

url

PublishedView

Published (Version of Record)

Abstract

Life Sciences & Biomedicine

Pharmacology & Pharmacy

Science & Technology

Veterinary Sciences

Methadone hydrochloride is a synthetic μ-opioid receptor agonist with potent analgesic properties. Oral methadone has been successfully used in human medicine and may overcome some limitations of other analgesics in equine species for producing analgesia with minimal adverse effects. However, there are no studies describing the pharmacokinetics (PK) of oral opioids in horses. The aim of this study was to describe the PK of orally administered methadone (0.1, 0.2 and 0.4 mg/kg) and physical effects in 12 healthy adult horses. Serum methadone concentrations were measured by gas chromatography/mass spectrometry at predetermined time points for 24 h, and PK parameters were estimated using a noncompartmental model. Physical effects were observed and recorded by experienced clinicians. No drug toxicity, behavioural or adverse effects were observed in the horses. The disposition of methadone followed first order elimination and a biphasic serum profile with rapid absorption and elimination phases. The PK profile of methadone was characterized by high clearance (Cl/F), small volume of distribution (Vd/F) and short elimination half-life (t1/2). The mean of the estimated t1/2 (SD) for each dose (0.1, 0.2 and 0.4 mg/kg) was 2.2 (35.6), 1.3 (46.1) and 1.5 (40.8), and the mean for the estimated Cmax (SD) was 33.9 (6.7), 127.9 (36.0) and 193.5 (65.8) respectively.

Details

Title: Pharmacokinetics of the injectable formulation of methadone hydrochloride administered orally in horses
Authors/Creators: R. L. Linardi - Louisiana State University
A. M. Stokes - Louisiana State University
S. A. Barker - Louisiana State University
C. Short - Louisiana State University
G. Hosgood - Louisiana State University
C. C. Natalini - Universidade Federal do Rio Grande do Sul
Publication Details: Journal of veterinary pharmacology and therapeutics, Vol.32(5), pp.492-497
Publisher: Wiley
Number of pages: 6
Grant note: Louisiana State University School of Veterinary Medicine VCS Corp and EHSP
Identifiers: 991005592760207891
Murdoch Affiliation: School of Veterinary Medicine
Language: English
Resource Type: Journal article

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

Source: InCites

Metrics

62 Record Views

13 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types: Domestic collaboration; International collaboration
Citation topics: 1 Clinical & Life Sciences; 1.43 Anesthesiology; 1.43.1642 Veterinary Anesthesia
Web Of Science research areas: Pharmacology & Pharmacy; Veterinary Sciences
ESI research areas: Plant & Animal Science