Abstract
Objective
To determine the optimal dose, serum concentrations and analgesic effects of intravenous
(IV) tramadol in the horse.
Study design
Two-phase blinded, randomized, prospective crossover trial.
Animals
Seven horses (median age 22.5 years and mean weight 565 kg).
Methods
Horses were treated every 20 minutes with incremental doses of tramadol HCl (0.1–1.6
mg kg−1) or with saline. Heart rate, respiratory rate, step frequency, head height, and sweating,
trembling, borborygmus and head nodding scores were recorded before and up to 6 hours
after treatment. In a second study, hoof withdrawal and skin twitch reflex latencies
(HWRL and STRL) to a thermal stimulus were determined 5 and 30 minutes, and 1, 2,
4 and 6 hours after bolus IV tramadol (2.0 mg kg−1) or vehicle. Blood samples were taken to determine pharmacokinetics.
Results
Compared to saline, tramadol caused no change in heart rate, step frequency or sweating
score. Respiratory rate, head height, and head nodding and trembling scores were transiently
but significantly increased and borborygmus score was decreased by high doses of tramadol.
Following cumulative IV administration of 3.1 mg kg−1 and bolus IV administration of 2 mg kg−1, the elimination half-life of tramadol was 1.91 ± 0.33 and 2.1 ± 0.9 hours, respectively.
Baseline HWRL and STRL were 4.16 ± 1.0 and 3.06 ± 0.99 seconds, respectively, and
were not significantly prolonged by tramadol.
Conclusion and clinical relevance
IV tramadol at cumulative doses of up to 3.1 mg kg−1 produced minimal transient side effects but 2.0 mg kg−1 did not provide analgesia, as determined by response to a thermal nociceptive stimulus.
Keywords
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References
- Evaluation of the effects of the opioid agonist morphine on gastrointestinal tract function in horses.Am J Vet Res. 2006; 67: 992-997
- Cardiopulmonary effects of buprenorphine in horses.Am J Vet Res. 2006; 67: 1675-1680
- Effects of buprenorphine on nociception and spontaneous locomotor activity in horses.Am J Vet Res. 2007; 68: 246-250
- Pharmacology of narcotic analgesics in the horse: selective blockade of narcotic-induced locomotor activity.Am J Vet Res. 1981; 42: 716-721
- Aerosolized albuterol sulfate used as a bronchodilator in horses with recurrent airway obstruction.Am J Vet Res. 1999; 60: 689-693
- Pharmacokinetics.in: Pharmacokinetics. Marcel Decker, New York1975: 281
- Pharmacokinetics 2. 2nd edn. Marcel Dekker, NY, USA1982: 409-447
- Pharmacokinetics of tramadol and its metabolites M1,M2, and M5 in horses following intravenous, immediate release (fasted/fed) and sustained release single dose administration.J Eq Vet Sci. 2007; 27: 481-487
- Clinical pharmacology of tramadol.Clin Pharmacokinet. 2004; 43: 879-923
- Differential effects of morphine and opioid analgesics on A and C fibre-evoked activity in ascending axons of the rat spinal cord.Brain. 1979; 171: 573-576
- Objective assessment of detomidine-induced analgesia and sedation in the horse.Eur J Pharmacol. 1988; 151: 1-8
- Pharmacokinetics of tramadol and the metabolite O-desmethyltramadol in dogs.J Vet Pharmacol Ther. 2004; 27: 239-246
- Animal models of nociception.Pharmacol Rev. 2001; 53: 597-652
- Tramadol: a new centrally acting analgesic.Am J Health Syst Pharm. 1997; 54: 643-652
- Acute antinociceptive responses in single and combinatorial opioid receptor knockout mice: distinct mu, delta and kappa tones.Eur J Neurosci. 2003; 17: 701-708
- Noncompartmental methods of drug characterization: statistical moment theory.J Am Vet Med Assoc. 1998; 213: 974-980
- Volume, clearance, and half-life.J Eq Vet Sci. 1998; 213: 1122-1127
- A comparison of preoperative tramadol and morphine for the control of early postoperative pain in canine ovariohysterectomy.Vet Anaesth Analg. 2003; 30: 220-228
- Visceral analgesia: effects of xylazine, butorphanol, meperidine, and pentazocine in horses.Am J Vet Res. 1985; 46: 2081-2084
- Pharmacokinetics of tramadol in children after i.v. or caudal epidural administration.Br J Anaesth. 2000; 84: 346-349
- Evaluation of the analgesic effects of epidurally administered morphine, alfentanil, butorphanol, tramadol, and U50488H in horses.Am J Vet Res. 2000; 61: 1579-1586
- Objective tests of analgesic drugs in ponies.Am J Vet Res. 1979; 40: 1082-1086
- Opioid and nonopioid components independently contribute to the mechanism of action of tramadol, an ‘atypical’ opioid analgesic.J Pharmacol Exp Ther. 1992; 260: 275-285
- Tramadol: metabolism and excretion in the horse.in: 13th International Conference of Racing Analysts and Veterinarians, Cambridge, UK. 2001: 453-457
- Tramadol: a review of its use in perioperative pain.Drugs. 2000; 60: 139-176
- Pharmacokinetics and adverse effects of butorphanol administered by single intravenous injection or continuous intravenous infusion in horses.Am J Vet Res. 2001; 62: 183-189
- Pharmacokinetics of tramadol in horses after intravenous, intramuscular and oral administration.J Vet Pharmacol Ther. 2008; 31: 60-65
- Impact of CYP2D6 genotype on postoperative tramadol analgesia.Pain. 2003; 105: 231-238
- Tramadol in the horse: a preliminary report on its detection, pharmacokinetics, and pharmacodynamic responses.in: Proceedings of the 17th International Conference of Racing Analysts and Veterinarians. 2009 (Antalya, Turkey.)
- Nociceptive responses to high and low rates of noxious cutaneous heating are mediated by different nociceptors in the rat: electrophysiological evidence.Pain. 1996; 68: 141-150
Article info
Publication history
Accepted:
December 31,
2008
Received:
July 24,
2008
Identification
Copyright
© 2009 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Inc. All rights reserved.
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- ErratumVeterinary Anaesthesia and AnalgesiaVol. 39Issue 6
- PreviewIn the publication “Intravenous tramadol: effects, nociceptive properties, and pharmacokinetics in horses” by Dhanjal JK, Wilson DV, Robinson E, Tobin TT and Dirokulu L, the name of the last author was incorrect (Dhanjal et al. 2009). It should be Levent Dirikolu. This has no influence on the meta-analysis itself.
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