Introduction: Spinal anesthesia is the safest during lower abdominal operations. Long-acting 
local anesthetics administered to the wound site or under the skin after surgery have been 
demonstrated to be effective for postoperative analgesia. The infiltration of wounds with local 
anesthetics seems not only to provide analgesia. It may also help to reduce the up-regulation 
of peripheral nociceptors that manifest as increased sensitivity to pain. It has been suggested that 
regional anesthetic techniques can reduce the postoperative stress response. Some additives to 
local anesthetics can hasten the onset of nerve block, prolong block duration, or reduce 
toxicity. Magnesium has been used as an effective adjuvant in postoperative pain and as its 
role as a physiological blocker of NMDA receptors in the sensitization process and hyperalgesia 
suppression. Another NMDA antagonist, Ketamine, has been raised to not only alleviate the 
patients' pain but also to lessen their needs for systemic opioids. Methods: A total of 100 
parturients underwent elective Caesarean sections were randomized into two equal groups of 
50 patients each using the computer-generated table. Ketamine group(K) received postoperative 
incisional local infiltration with a total volume of 20 ml of 10 ml bupivacaine 0.5%, 25 mg 
ketamine (0.5 ml) plus saline 0.9% (9.5 ml) and magnesium sulfate group(M) who received 
postoperative incisional local infiltration with a total volume of 20 ml of 10 ml bupivacaine 
0.5 %, 750 magnesium sulfate (7.5 ml) plus saline 0.9% (2.5 ml). Results: We found that the
use of magnesium sulfate in a dose of (750 mg) as an adjuvant to bupivacaine provided better 
postoperative analgesia than the usage of low dose ketamine in a dose of (25 mg) as an adjuvant 
to bupivacaine in subcutaneous infiltration in the cesarean wound .