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. After continuous administration of tetrandrine, accumulation of the drug in liver, lung, kidney, and adrenal gland was observed. The amount of drug stored in the organs increased with the quantity of drug given to the animal.