Comparative effects of Bay Va 1470 (xylazine) , promazine and halothane on serum electrolytes in the horse
Short, C.E.; Tumbleson, M.E.; Merriam, J.G.
Veterinary Medicine-Small Animal Clinician 67(7): 747-750
1972
ISSN/ISBN: 0042-4889 PMID: 4483116 Document Number: 56969
Thirty-seven horses were used to study the effects of xylazine and to compare its effects with those of promazine, both alone and in combination with thiamylal sodium and halothane. At 0.5 mg/lb i/v, xylazine caused only slight reductions in cardiac and respiratory rates, the maximum effect of the drug was achieved within 6 minutes and the effect remained strong for 45 minutes. When given to mares at weaning time it had a calming effect and reduced the period of excitement. When it was given as a pre-anaesthetic, the reduction in the dosage of thiamylal was similar to that made possible with promazine. After a dose of xylazine alone, electrolyte values were affected only by a slight decline in K levels; proteins were unchanged, as were SGOT and alkaline phosphatase levels. Glucose values increased significantly immediately after the administration of the combination-xylazine-thiamylal-halothane. It is concluded that xylazine is as safe as promazine for tranquillization and pre-anaesthesia in horses.