A field survey was made on the combined use of xylazine and butorphanol for standing equine restraint (52 practitioner university clinics). A suggested initial dose range for xylazine and butorphanol was 0.34-0.74 mg/kg body weight and 0.007-0.057 mg/kg, respectively. It was found that the dose had to be adjusted depending on the individual response, the level of sedation and analgesia required and the type of diagnostic or surgical procedure to be performed. Increased dose increased the side effects, but the frequency and severity of the rapid effects can be reduced if butorphanol is administered 3-5 min after xylazine. The drug combination can be used to induce local anaesthesia. The onset of xylazine sedation occurred after 2-5 mins and analgesia from butorphanol after 5-10 mins. The duration of good analgesia and sedation was 30-35 mins. The combination of xylazine and butorphanol allows for a reduction in the dose of butorphanol, and xylazine acts in a complementary way to reduce some of the central nervous system signs that may be produced by butorphanol.
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