Toxicity of Na salicylate was compared by oral or IV route in cynomolgus monkeys. Three males and females were orally treated with escalating three dosages with a recovery period of 7 days; 500, 750, 1125 mg/kg. For IV route, 12 males and 12 females (3 animals per group) were treated with 3 dosages; 0 mg/kg, 138 mg/kg, 275 mg/kg, 550 mg/kg, respectively. The findings were as follows: oral emetic dose was between 500 mg/kg and 750 mg/kg, showing more than 750 mg/kg dosage did not show any clinical sign except vomiting. The IV emetic dose was about 275 mg/kg, and the approximate lethal dose for IV route was between 275 mg/kg and 500 mg/kg.