Medetomidine-vatinoxan and acepromazine-methadone: comparison of sedative and cardiovascular properties as preanaesthetic medication in healthy dogs

Q: What was the primary objective of the study?

To compare medetomidine-vatinoxan with acepromazine when used as preanaesthetic medication in a randomized, blinded clinical study in healthy dogs.

Q: How were sedation and treatment endpoints assessed?

Sedation score (SS, 0–12) and visual analogue scale (VAS, 0–100 mm) were measured every 5 minutes until SS≥6 or 30 minutes after treatment.

Q: What were the main findings regarding sedation onset and cardiovascular interventions?

Dogs receiving medetomidine-vatinoxan achieved SS≥6 faster (median 5 minutes) than acepromazine (median 20 minutes). The number of dogs requiring interventions for hypotension, bradycardia, and/or bradyarrhythmias did not significantly differ between groups.

Sep 30, 2026

Uploaded by Riley West

Objective comparison of medetomidine-vatinoxan versus acepromazine as preanaesthetic medication in healthy dogs for elective ovariectomy. Healthy client-owned dogs (n=25) received intramuscular methadone (0.2 mg/kg) with either medetomidine (0.01 mg/kg) plus vatinoxan (0.2 mg/kg; group MV) or acepromazine (0.02 mg/kg; group A). Sedation (SS 0–12) and pain/discomfort-related response (VAS 0–100 mm) were assessed every 5 minutes until SS≥6 or 30 minutes elapsed, then anaesthesia was induced with propofol and maintained with sevoflurane. Cardiovascular interventions were recorded; Student’s t test, Mann–Whitney U, and Fisher’s exact test were used.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages11

Reading Time28 min

AccessFree to download

Abstract

Background

Methods

Results

Conclusions

Background

Preanaesthetic sedation in veterinary medicine

Alpha-2-adrenoceptor agonists and vatinoxan

Acepromazine effects

Pekkola et al. Acta VeterinariaScandinavica (2026) 68:1 Acta Veterinaria Scandinavica [https://doi.org/10.1186/s13028-025-00844-3](https://doi.org/10.1186/s13028-025-00844-3) RESEARCH Open Access Medetomidine-vatinoxan-methadone and acepromazine-methadone: comparison of sedative and cardiovascular properties asa preanaesthetic medication in healthy dogs Vuokko Pekkola 1*, Ira Kal lio-Kujala 1, Marja Raekall io2, Jaan Lepajõe 1 and Kati Salla2 Abstract Background Medetomidine-vatinoxan is a relatively new medicinal product indicated for sedation of healthy dogs. Vatinoxan alleviates medetomidine-induced bradycardia and peripheral vasoconstriction in dogs, but when used asa preanaesthetic medication, it has been shown to cause more hypotension during general anaesthesia compared to medetomidine alone. Our aim was to compare medetomidine-vatinoxan to acepromazine when used as apreanaesthetic medication in a randomised, blinded, clinical study. Healthy client-owned dogs (n = 25) scheduled for elective ovariectomy were randomly assigned to receive 0.2 mg/kg intramuscular methadone combined with either 0.01 mg/kg medetomidine and 0.2 mg/kg vatinoxan (group MV, n = 13) or 0.02 mg/kg acepromazine (group A, n = 12) . A sedation scale (SS, range 0–12) and visual analogue scale (VAS, range 0–100 mm) were applied to assess sedation every 5 min until one of the following endpoints was reached: the SS was ≥ 6 or30 min from treatment had passed. After this, general anaesthesia was induced with propofol and maintained with sevoflurane vaporised in oxygen. The need for cardiovascular interventions according to current guidelines was recorded. Statistical comparisons were performed with Student’s t test, the Mann‒Whitney U test and Fisher’s exact test. P-values < 0.05 were considered statistically significant. Results The median (range) time to achieve an SS ≥6 was 5 (5–10) minutes in the MV group and 20 (10–25) minutes in the A group (P-value < 0. 001) . The number of dogs needing interventions for hypotension, bradycardia and/or bradyarrhytmias (7 in group MV, 8 in group A) did not significantly differ between the groups. Conclusions When used as a preanaesthetic medication in combination with methadone, medetomidine-vatinoxan causes faster onset of sedation, without statistically significant differences in cardiovascular interventions, compared to acepromazine. Keywords Alpha-2-adrenoceptor agonists, Hypotension, MK-467, Premedication, Sedation *Correspondence: Vuokko Pekkola [vuokko.pekkola@helsinki.fi](vuokko.pekkola@helsinki.fi) 1Veterinary Teaching Hospital, Faculty of Veterinary Medicine, University of Helsinki, PO BOX 57, Helsinki FI-00014, Finland 2Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, PO BOX 57, Helsinki FI-00014, Finland © The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit [http://creativecommons.org/l](http://creativecommons.org/l)icenses/by/4.0/. The Creative Commons Public Domain Dedication waiver ([http://creativecommons.org/publicdomain/zero/1.0/](http://creativecommons.org/publicdomain/zero/1.0/)) applies to the data made available in this article, unless otherwise state

FAQs

What was the primary objective of the study?

To compare medetomidine-vatinoxan with acepromazine when used as preanaesthetic medication in a randomized, blinded clinical study in healthy dogs.

How were sedation and treatment endpoints assessed?

Sedation score (SS, 0–12) and visual analogue scale (VAS, 0–100 mm) were measured every 5 minutes until SS≥6 or 30 minutes after treatment.

What were the main findings regarding sedation onset and cardiovascular interventions?

Dogs receiving medetomidine-vatinoxan achieved SS≥6 faster (median 5 minutes) than acepromazine (median 20 minutes). The number of dogs requiring interventions for hypotension, bradycardia, and/or bradyarrhythmias did not significantly differ between groups.

Sep 30, 2026

Uploaded by Riley West