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Open veterinary journal2025; 15(7); 2938-2947; doi: 10.5455/OVJ.2025.v15.i7.5

Sedative effects of detomidine and midazolam combination in horses.

Abstract: The combination of detomidine and midazolam may provide safer sedation with muscle-relaxant effects, which are particularly necessary during standing procedures. Unassigned: Thus, the objective of this study was to evaluate the sedative and muscle-relaxant effects of the detomidine/midazolam combination in horses through a pharmacodynamic study. Unassigned: Five horses were used and subjected to four experimental protocols: 15 µg/kg of detomidine (D15); a combination of detomidine (15 µg/kg) with 25 µg/kg (DM25), 50 µg/kg (DM50), or 75 µg/kg (DM75) of midazolam administered intravenously. The sedative and muscle-relaxant effects, as well as physiological parameters, were evaluated and statistically analyzed. Unassigned: All protocols resulted in a decrease in head height, although no significant difference was observed among them. The acoustic stimulus response and tongue tone relaxation showed significant effects in the global analysis. Unassigned: This study contributes to our understanding of the application of this combination in equine sedation protocols.
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Publication Date: 2025-07-31 PubMed ID: 41036345PubMed Central: PMC12483408DOI: 10.5455/OVJ.2025.v15.i7.5Google Scholar: Lookup
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  • Journal Article

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.

Overview

  • This study investigated how combining detomidine and midazolam affects sedation and muscle relaxation in horses to improve safety and comfort during standing procedures.
  • The researchers compared different doses of midazolam combined with a fixed dose of detomidine to evaluate the resulting sedative and muscle-relaxant effects along with physiological changes.

Introduction and Objective

  • The study focuses on the combination of two drugs: detomidine, an alpha-2 adrenergic agonist typically used for sedation in horses, and midazolam, a benzodiazepine known for muscle relaxation and sedation.
  • Standing procedures in horses require effective sedation combined with muscle relaxation to minimize stress and risk of injury without deep anesthesia.
  • The study aimed to evaluate how combining detomidine with varying doses of midazolam influences sedative depth and muscle relaxation compared to detomidine alone.

Methods

  • Five horses were used as subjects in the experiment, ensuring repeated measures across different sedation protocols.
  • Four experimental protocols were tested intravenously:
    • D15: Detomidine alone at 15 µg/kg
    • DM25: Detomidine (15 µg/kg) + Midazolam (25 µg/kg)
    • DM50: Detomidine (15 µg/kg) + Midazolam (50 µg/kg)
    • DM75: Detomidine (15 µg/kg) + Midazolam (75 µg/kg)
  • Parameters measured included:
    • Head height – to assess sedation depth (lower head height indicates stronger sedation)
    • Response to an acoustic stimulus – to evaluate sedation responsiveness
    • Tongue tone relaxation – as an indicator of muscle relaxation
    • Physiological parameters – likely including heart rate, respiratory rate, etc., for monitoring safety
  • Data were statistically analyzed to identify significant effects of the drug combinations compared to detomidine alone.

Results

  • All treatment protocols reduced head height, indicating sedation occurred in all groups.
  • However, no statistically significant difference in head height was observed among the protocols, meaning adding midazolam did not further decrease head height beyond detomidine alone.
  • Significant effects were observed in:
    • Acoustic stimulus response – indicating variations in sedation depth or responsiveness based on midazolam dose.
    • Tongue tone relaxation – showing enhancements in muscle relaxation with midazolam addition.
  • The combination protocols seemed to provide better muscle relaxation compared to detomidine alone, which is important for standing procedures where muscle tone must be reduced to prevent sudden movements or stress.

Conclusions

  • The combination of detomidine and midazolam may enhance muscle relaxation without significantly increasing the sedative depth as measured by head height.
  • This combination therefore has potential for safer and effective sedation protocols in horses during standing procedures, where muscle relaxation is key.
  • The study improves understanding of how adjusting the midazolam dose alongside detomidine affects sedation and muscle tone in horses.

Significance and Applications

  • Using detomidine alone provides sedation but may not fully address muscle relaxation needs during standing surgeries or examinations.
  • Adding midazolam can optimize sedation protocols by combining sedative and muscle-relaxant effects safely.
  • These findings can help veterinarians tailor sedation plans to improve horse welfare and procedural safety.

Cite This Article

APA
Gomes ÉR, Felix LA, Gonzaga LWF, da Silva NFD, Soares BCF, de Almeida JVFC, Souza GP, Pereira RN, Taffarel MO, Ferrante M. (2025). Sedative effects of detomidine and midazolam combination in horses. Open Vet J, 15(7), 2938-2947. https://doi.org/10.5455/OVJ.2025.v15.i7.5

Publication

Open veterinary journal
ISSN: 2218-6050
NlmUniqueID: 101653182
Country: Libya
Language: English
Volume: 15
Issue: 7
Pages: 2938-2947

Researcher Affiliations

Gomes, Érika Ribeiro
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Felix, Larissa Alexsandra
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Gonzaga, Lucas Wamser Fonseca
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
da Silva, Naira Fernanda Dias
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Soares, Bruna Christina Fernandes
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
de Almeida, João Vitor Fernandes Cotrim
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Souza, Gabriela Pereira
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Pereira, Rodrigo Norberto
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.
Taffarel, Marilda Onghero
  • Department of Veterinary Medicine, State University of Maringá, Maringá, Brazil.
Ferrante, Marcos
  • Department of Veterinary Medicine, Federal University of Lavras, Lavras, Brazil.

MeSH Terms

  • Animals
  • Midazolam / administration & dosage
  • Midazolam / pharmacology
  • Horses / physiology
  • Hypnotics and Sedatives / pharmacology
  • Hypnotics and Sedatives / administration & dosage
  • Imidazoles / administration & dosage
  • Imidazoles / pharmacology
  • Male
  • Female
  • Drug Therapy, Combination / veterinary

Conflict of Interest Statement

The authors declare that they have no conflicts of interest.

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