Intravenous, but not oral, metoclopramide increases rate ofabsorption of diazepam and raises its maximum plasma levels.Metoclopramide increases rate of absorption of zopiclone.
Clinical evidence,mechanism, importance and management
Intravenous metoclopramide increased peak plasma levels of diazepam by 38 % and increased rate of absorption (peak levels occurred at 30 minutes instead of 60 minutes),(See reference number 1) but in 6 healthy subjects oral metoclopramide 10mg did not increase rate of absorption of oral diazepam
0.2 mg/kg (See reference number 2). The reason is not understood. The clinical importance of this interaction is not known,but it is probably small.
The rate of absorption of a single 7.5mg dose of oral zopiclone was increased by metoclopramide 10mg given intravenously to 12 healthy subjects. This was presumably because these drugs alter gut motility. Metoclopramide increased mean plasma levels of zopiclone, from 22.7 to 44.4 nanograms/mL at 1 hour,and from 49.3 to 59.6 nanograms/mL at 2 hrs (See reference number 3). The clinical importance of these findings is not known.
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