The Sound of Evolution
Metoclopramide
Mechanism of action:
Metoclopramide is a dopamine D₂ receptor antagonist. Metoclopramide can cross the blood-brain barrier and block dopamine D₂ receptors in the chemoreceptor trigger zone of the medulla, thereby inhibiting dopamine-mediated emetic signaling. In the gastrointestinal tract, metoclopramide blocks D₂ receptors that inhibit acetylcholine release, leading to increased parasympathetic acetylcholine release and enhanced gastrointestinal motility.
Reference(s):
1. Tonini M et al. (1995). Therapeutic potential of drugs with mixed 5-HT4 agonist/5-HT3 antagonist action in the control of emesis. Pharmacol Res.
2. Lee A et al. (2010). Metoclopramide in the treatment of diabetic gastroparesis. Expert Rev Endocrinol Metab.
3. van der Meer YG et al. (2014). Should we stop prescribing metoclopramide as a prokinetic drug in critically ill patients? Crit Care.