High pressure liquid chromatographic analysis of metoclopramide in serum

Metoclopramide has recently been approved at dose levels of 1 to 2 mg/kg for the treatment of nausea and vomiting resulting from cancer chemotherapeutic agents. A rapid, sensitive reverse phase HPLC quantitative procedure for metoclopramide in serum is described. The method involves a single-step extraction of metoclopramide and disopyramide (internal standard) from alkalinized serum into benzene and utilizes a reverse-phase C-8 system with a mobile phase of 11:22:66, methanol: acetonitrile: pH 3.7 acetate buffer, and UV detection at 268 nm. The method is highly reproducible and has a limit of sensitivity of 2.5 ng/ml from a 2.0 ml serum sample. The method has been successfully applied to clinical pharmacokinetic studies involving administration of IV oral metoclopramide to cancer patients receiving highly emetogenic cis-diamminedichloroplatinum.