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Evaluation of Medetomidine Dose Variations on Tiletamine-Zolazepam and Tramadol Anesthetic Combination in Dogs
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Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
2
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Jeju National University, Jeju 63243, Republic of Korea
3
Department of Veterinary Surgery, College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea
*
Author to whom correspondence should be addressed.
Animals 2025, 15(23), 3419; https://doi.org/10.3390/ani15233419
Submission received: 26 September 2025
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Accepted: 24 November 2025
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Published: 26 November 2025
(This article belongs to the Special Issue Developments in Therapeutic Drugs for Pain Management in Animals)
Simple Summary
Veterinary anesthesia often requires combining multiple drugs to achieve safe and effective anesthesia for short procedures in dogs. This study evaluates an anesthetic combination of tiletamine-zolazepam, tramadol, and medetomidine (TZTM), focusing on how different medetomidine doses affect anesthesia depth, analgesia, and cardiovascular stability. The combination excludes highly regulated opioids, making it more accessible and easier to prepare. Three formulations were tested: one without medetomidine and two containing different concentrations. The physiological parameters, including heart rate, blood pressure, respiratory rate, oxygen saturation, analgesic effect, and recovery quality, were assessed. The results indicated that medetomidine dose-dependently prolonged anesthesia and analgesia while transiently reducing heart rate and oxygen saturation. Higher medetomidine doses improved recovery quality, suggesting its suitability for stable and balanced sedation. However, due to its cardiovascular effects, careful patient selection is necessary, particularly in individuals with pre-existing heart conditions. These findings highlight TZTM as a practical alternative for short veterinary procedures, provided that appropriate monitoring is implemented.
Abstract
This study evaluated the effects of varying medetomidine doses on a tiletamine-zolazepam and tramadol anesthetic combination in dogs. The objective was to assess how medetomidine influences anesthesia depth, cardiovascular function, and recovery quality. Dogs were assigned to one of three treatment groups: tiletamine-zolazepam and tramadol without medetomidine (TZT), additional 10 µg/kg medetomidine (TZTM10), or additional 20 µg/kg medetomidine (TZTM20). Each dog received an intramuscular injection of 0.1 mL/kg of the designated solution. The formulation for TZT contained 25 mg/mL tiletamine and zolazepam and 40 mg/mL tramadol, while TZTM10 and TZTM20 received the same solution with additional medetomidine at 100 and 200 µg/mL, respectively. Onset time, anesthetic time, analgesic time, recovery quality, and physiological parameters, including heart rate, blood pressure, respiratory rate, oxygen saturation, and body temperature, were evaluated. Medetomidine extended analgesic time in a dose-dependent manner and improved recovery quality while maintaining stable respiratory function. While TZT provided adequate anesthesia for minor non-invasive procedures, the inclusion of medetomidine in TZTM resulted in enhanced anesthetic stability for simple surgical procedures such as gonadectomy. These findings suggest that TZTM20 is a viable anesthetic protocol, though careful patient monitoring remains essential due to its cardiovascular effects.
Keywords:
α2-adrenergic agonist; dissociative; dog; injectable anesthesia; medetomidine; opioid
