Validated liquid chromatography-tandem mass spectrometry method for simultaneous determination of clopamide, reserpine and dihydroergotoxine: Application to pharmacokinetics in human plasma.

•Determination of clopamide, reserpine and dihydroergotoxine in plasma by LC–MS/MS.•Separation of two isomers by a short chromatographic column.•Liquid-liquid extraction was used to obtain cleaner samples.•Autosampler rinsing solvents were used to flush out the carry-over.•The method is useful to study the pharmacokinetic profile of the selected drugs.