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

AIM This research was carried out to compare magnesium sulfate (MgSO4) with isotonic saline in terms of pain control after herniorrhaphy. PATIENTS & METHODS 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 MgSO4 in 2 cc of isotonic saline and 4 cc of isotonic saline, respectively. RESULT 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). CONCLUSION MgSO4 increased the potency of morphine thereby reducing the amount of postoperative pain killer needed.