目的 研究光纤药物溶出度实时测定（ FODT ）仪监测复方磺胺甲唑片的溶出度。 方法 用 FODT 法建立多元线性回归曲线，监测不同厂家生产的复方磺胺甲唑片的溶出度，提取溶出曲线、药物溶出 70% 所需的时间及溶出 30 min 时的累积溶出百分率，并将后者与中国药典法结果进行比较。 结果 多元线性回归曲线拟合优度佳，合格和不合格药品的溶出结论均与药典法一致， FODT 法尚可提供溶出曲线和药物溶出 70% 所需的时间，弥补了 HPLC 单点测定的不足。 结论 FODT 法经过完善，可以更好地用于复方磺胺甲唑片溶出度的检查。

OBJECTIVE To determine the dissolution rate of compound sulfamethoxazole tablets with the instrument of fiber-optic in situ dissolution testing (FODT). METHODS By the software in FODT instrument,the multiple regression was established. The dissolution rates of compound sulfamethoxazole tablets produced by the different industries were monitored. The dissolution curves, the time of 70% dissolution and the accumulative dissolution percentages at 30 min were obtained. The latter was compared with that measured by the method provided in Ch.P. RESULTS The drug concentrations were obtained by the multiple linear regression curve. All results of the drug’s dissolution rate by FODT were identical to ones of Ch.P. With FODT, the dissolution curve, the time of 70% dissolution of the drugs were also measured. The results had a good remedy for the defects of one point monitoring with HPLC. CONCLUSION The method of FODT may be better than that of Ch.P for the determination of the dissolution rate of compound sulfamethoxazole tablets.