Tolazine Injection is a reversing agent for the sedative Xylazine. Tolazine may be used in horses when it is desirable to reverse the effects of sedation and analgesia caused by Xylazine. The dosage is typically recommended at 4.0 mg/kg body weight (4 ml/100 kg or 4 ml/220 lbs.) to reverse the sedative effects of Xylazine. The carefully calculated dose of Tolazine should be given slowly by IV injection at the rate of approximately 1 ml per second. 100 mg/ml Tolazine.