Studies of the chronic toxicity of tetrandrine in dogs: an inhibitor of silicosis.

Dogs administered tetrandrine at low dose (3 mg/kg) and medium dose (10 mg/kg) levels showed no toxic changes. Administration of the drug at a high dose level (40 mg/kg) for 2 months may induce focal necrosis of liver cells, abnormal liver function, and acceleration of erythrocyte sedimentation rate. After the dogs had received tetrandrine for 6 months continuously, necrosis of liver tissue appeared.