Metoclopramide reduces the induction dose of propofol

Background: Metoclopramide has been shown to reduce the dose of thiopentone required for induction of anaesthesia. When propofol is used, there have been conflicting results with one small study showing a reduction in the anaesthetic dose and one study failing to demonstrate any effect.
Methods: Two groups of 30 patients were studied. The patients were randomised to receive either saline 0.03 ml/mg or metoclopramide 0.15 mg/kg 5 min before a manual injection of propofol at a set rate.
Results: This study shows a reduction in the dose of propofol required for the induction of general anaesthesia following an intravenous dose of metoclopramide. The induction dose of propofol was reduced by 24%.
Conclusions: The mechanism of reduction of propofol dose by metoclopramide is unknown; it may involve GABA or result from a more complex interaction involving dopamine blockade by metoclopramide.