magnesium and morphine

Q: Intravenous Magnesium (IV Mg) potentiates the opioid effect? 

A) True

B) False

Answer: A

IV Mg is considered a usual adjuvant with opioids. It potentiates the opioid effect and so reduces it's dose requirement. This is due to its antagonist property of N-methyl-D-aspartate(NMDA) receptor. If utilized in perioperative time, it reduces opioid consumption as well as pain scores in first 24 hours postop period. IV Mg can be given as bolus and/or continuous infusion.

#pharmacology

#pain

#surgical-critical-care

References:

1. Albrecht E, Kirkham KR, Liu SS, Brull R. Peri-operative intravenous administration of magnesium sulphate and postoperative pain: a meta-analysis. Anaesthesia 2013; 68:79.

2. De Oliveira GS Jr, Castro-Alves LJ, Khan JH, McCarthy RJ. Perioperative systemic magnesium to minimize postoperative pain: a meta-analysis of randomized controlled trials. Anesthesiology 2013; 119:178.