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The Veterinary clinics of North America. Equine practice2010; 26(3); 515-532; doi: 10.1016/j.cveq.2010.07.003

Alpha-2 agonists as pain therapy in horses.

Abstract: Alpha-2 agonists, such as xylazine, clonidine, romifidine, detomidine, medetomidine, and dexmedetomidine, are potent analgesic drugs that also induce physiologic and behavioral changes, such as hypertension, bradycardia, atrioventricular block, excessive sedation and ataxia, all of which can potentially limit their systemic use as analgesics in some clinical cases. The use of medetomidine and dexmetomidine has been introduced for equine anesthesia/analgesia, and although not approved in this species, their increased specificity for alpha-2 receptors may offer some potential advantages over the traditional alpha-2 agonists. Similarly, other routes of administration and benefits of alpha-2 agonists are recognized in the human and laboratory animal literature, which may prove useful in the equine patient if validated in the near future. This review presents this relevant information.
Copyright © 2010 Elsevier Inc. All rights reserved.
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Publication Date: 2010-11-09 PubMed ID: 21056297DOI: 10.1016/j.cveq.2010.07.003Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research is based on the use of alpha-2 agonists, a group of drugs, as a possible pain remedy in horses. However, the drugs potentially cause side effects such as hypertension and excessive sedation, which might limit its use. Despite this, some alpha-2 agonists are seeing use in equine anesthesia and could potentially have advantages over traditional alternatives.

Alpha-2 agonists as potential analgesics

  • The study primarily concerns the use of alpha-2 agonists as therapy for pain in horses. These compounds, including xylazine, clonidine, romifidine, detomidine, medetomidine, and dexmedetomidine, are powerful pain relievers.
  • Alpha-2 agonists are not only recognized for their ability to numb pain, but they can also cause physiological and behavioral changes. These changes can be both positive and negative, depending on the situation.

Side effects of alpha-2 agonists

  • One significant factor limiting the widespread use of alpha-2 agonists as systemic analgesics are some of the side effects associated with these medications. These include hypertension (high blood pressure), bradycardia (slow heart rate), atrioventricular block (a type of heart block), excessive sedation, and ataxia (lack of muscle control).

Usage in equine anaesthesia

  • Some alpha-2 agonists, namely medetomidine and dexmetomidine, have made their way into the field of equine anesthesia and analgesia. Although these drugs are not yet approved for use in this species, thanks to their increased specificity for alpha-2 receptors, they might represent an upgrade over conventional alpha-2 agonists.

Scope for future applications

  • The human and lab animal literature acknowledges other routes of administering alpha-2 agonists, and further benefits that could be potentially useful for horses. Future validation of these applications could pave the way for more optimal use of alpha-2 agonists in treating equine pain.
  • This research paper aims to present all the relevant information and evidence regarding the use of alpha-2 agonists in treating pain in horses, in a bid to explore an alternative and potentially more effective mode of treatment.

Cite This Article

APA
Valverde A. (2010). Alpha-2 agonists as pain therapy in horses. Vet Clin North Am Equine Pract, 26(3), 515-532. https://doi.org/10.1016/j.cveq.2010.07.003

Publication

The Veterinary clinics of North America. Equine practice
ISSN: 1558-4224
NlmUniqueID: 8511904
Country: United States
Language: English
Volume: 26
Issue: 3
Pages: 515-532

Researcher Affiliations

Valverde, Alexander
  • Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, 50 Stone Road, ON, Canada N1G 2W1. valverde@uoguelph.ca

MeSH Terms

  • Adrenergic alpha-2 Receptor Agonists / adverse effects
  • Adrenergic alpha-2 Receptor Agonists / pharmacology
  • Adrenergic alpha-2 Receptor Agonists / therapeutic use
  • Analgesia / veterinary
  • Analgesics / adverse effects
  • Analgesics / pharmacology
  • Analgesics / therapeutic use
  • Animals
  • Horse Diseases / drug therapy
  • Horses
  • Pain / drug therapy
  • Pain / veterinary

Citations

This article has been cited 15 times.
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