Alpha-2-Adrenoceptor agonists in Veterinary Practice

Since the first a2- adrenoceptor agonist xylazine (Rompun) was synthesized in 1962 in Germany, and subsequent development of others in this group, a2-adrenoceptor agonists have been used for decades for their sedative, analgesic and muscle relaxant properties in laboratory, domestic and wild animal species. Although drugs in this group induce physiologic alterations in many species whose magnitude depends on the dose, rate of administration and concomitantly administered drugs, they have proven to be safe adjunctive agents in augmenting central nervous system depression, analgesia and muscle relaxation in healthy patients. One of the more significant advances in veterinary anesthesiology during the last decade has been the utilization of antagonists for the reversal of injectable anesthetic regimens. Most notable of these is the clinical application of a2-antagonists such as yohimbine, telazoline, midazoxam, and atipamazole for the reversal of the sedative –muscle relaxant action actions induced by xylazine and other a2- adrenoceptor agonists. This advance has made the use of drugs in this group safer and they will continue to play an important role in the evolution and development of reliable synergistic receptor mediated analgesia and anesthesia. This paper looks at the role a2-adrenoceptor agonists have played and continue to play in veterinary practice. The Kenya Veterinarian Vol. 22 2001: pp. 82-9