There was no significant difference in FI of CRMS and IRMS. The satisfied analgesic effect was observed at the steady state concentration of morphine in cancer patients with moderate or severe pain.

• CRMS和IRMS的血药浓度在第4天已达稳态，并出现良好的临床镇痛效应，两种制剂的波动系数无显著性差异。