Oral Ketamine Provides Superior Postoperative Analgesia to Tramadol and Paracetamol After Caesarean Section: A Prospective Comparative Study

Abstract

Background: Effective postoperative analgesia is essential for optimal recovery after caesarean section (CS), particularly within Enhanced Recovery After Caesarean Surgery (ERACS) pathways. Opioid-sparing strategies are increasingly prioritized, especially in breastfeeding women and in resource-limited settings where access to advanced analgesic techniques may be restricted. Although oral ketamine, tramadol, and paracetamol are widely used, comparative evidence on their postoperative effectiveness in post-CS patients remains limited.

Methods: This prospective, randomized, single-blind study included forty-five ASA I–II patients undergoing elective CS under spinal anaesthesia. Participants were randomized into three equal groups to receive oral ketamine 50 mg, tramadol 100 mg, or paracetamol 500 mg, administered 30 minutes after surgery or once oral fluids were tolerated. Subsequent doses were given every eight hours for 24 hours. Pain intensity was assessed using the 0–10 Numeric Rating Scale (NRS) at 2, 8, 16, and 24 hours by trained paramedical staff. Rescue analgesia (intravenous fentanyl) and adverse effects were recorded. Intergroup comparisons used ANOVA, and intragroup trends were analyzed using the Wilcoxon test.

Results: All forty-five participants completed the study with comparable baseline characteristics. Oral ketamine produced significantly lower NRS scores at all time points compared with tramadol and paracetamol (p < 0.05). No participants in the ketamine group required rescue fentanyl, whereas 13.3% in the tramadol group and 26.7% in the paracetamol group required additional analgesia. Adverse effects were mild, with no hallucinations or severe reactions observed. The safety and analgesic superiority of ketamine were not attributable to dosing inequivalence, as all drugs were administered within standard therapeutic ranges and patient BMI and ideal body weight were similar across groups.

Conclusion: Oral ketamine provides superior analgesia, lower rescue opioid requirement, and a favourable safety profile compared with oral tramadol and paracetamol in the first 24 hours after caesarean section. Its affordability, ease of administration, and compatibility with breastfeeding make it an attractive option for ERACS protocols, particularly in low-resource settings. These findings support the integration of low-dose oral ketamine into multimodal postoperative pain management for CS, although further research with extended monitoring is warranted to refine dosing and long-term safety.