Objective: To compare the use of diclofenac intramuscular single dose to decrease pain in post operative Caesarean section with none used.
Study design: A double blind randomized controlled trial.
Setting: Department of Obstetrics and Gynecology, Ranong Hospital.
Subjects: Sixty-four patients who underwent post operative Caesarean section in Ranong Hospital from October 2003 to March 2004.
Intervention: The subjects were randomized by allocation to receive diclofenac intramuscular or placebo, both groups received morphine by Patient Controlled Analgesia (PCA).
Main outcome measures: Amount of morphine sulfate used, in both groups by Patient Controlled Analgesia (PCA) and level of pain using Visual Analog Score (VAscore).
Results: Morphine was used significantly less in the group of patients who had diclofenac intramuscular single dose in post operative Caesarean section but the level of pain was not significantly different.
Conclusion: A single dose of diclofenac intramuscularly decreases the use of morphine during the in post operative period of Caesarean section.

Keywords: Diclofenac, Morphine, Patient Controlled Analgesia, Caesarean section, Visual Analog Score