Simultaneous Determination of Centchroman and Tamoxifen Along with Their Metabolites in Rat Plasma Using LC–MS/MS

Aim: Tamoxifen and centchroman are two non-steroidal, selective estrogen receptors modulators, intended for long term therapy in the woman. Because of their wide spread use, there is a possibility of co-prescription of these agents. Materials & Methods: We studied the probable pharmacokinetic interaction between these agents in breast cancer model rats. A simple, sensitive and rapid LC-ESI-MS/MS method was developed and validated for the simultaneous determination of tamoxifen, centchroman and their active metabolites. Results: The method was linear over a range of 0.2–200 ng/ml. All validation parameters met the acceptance criteria according to regulatory guidelines. Conclusion: LC–MS/MS method for determination of tamoxifen, centchroman and their metabolites was developed and validated. Results show the potential of drug–drug interaction upon co-administration these two marketed drugs.