Andrographolide from the herb Andrographis paniculata (whole plant) per se produces a significant dose (1.5-12 mg/kg) dependent choleretic effect (4.8-73%) as evidenced by increase in bile flow, bile salt, and bile acids in conscious rats and anaesthetized guinea pigs. The paracetamol induced decrease in volume and contents of bile was prevented significantly by andrographolide pretreatment. It was found to be more potent than silymarin, a clinically used hepatoprotective agent.