Physiologic alterations induced by xylazine depend on the dose, rate, and r
oute of administration and are influenced by the concomitant administration
of other classes of drugs. When these factors are appropriately considered
, alpha(2)-adrenoceptor agonists are safe drugs for inducing narcosis, anal
gesia, and muscle relaxation in healthy fasted ruminants. Tolazoline has pr
oven to be a safe, effective antagonist for xylazine-induced sedation and o
ther actions when the proper dose is administered.