Effect of magnesium sulfate on morphine activity retention to control pain after herniorrhaphy

This research was carried out to compare magnesium sulfate (MgSO ) with isotonic saline in terms of pain control after herniorrhaphy. A randomized double-blind study, in which the patients were blind to all. A total of 100 patients who were candidates of herniorrhaphy were randomized into two groups: experimental and control (50 patients in each). Anesthesia was induced with 20% of 4 cc of morphine. The experimental and control group received postoperative 20% of 2 cc MgSO in 2 cc of isotonic saline and 4 cc of isotonic saline, respectively. The administration of postoperative morphine in control group 0.79 ± 1.48 mg was significantly higher to the experimental group 0.17 ± 0.63 mg during the first 24 h (p = 0.01). MgSO increased the potency of morphine thereby reducing the amount of postoperative pain killer needed.