Caesarean section rates have increased over the past 3 decades. Caesarean section is often associated with acute post-operative abdominal pain and medications containing codeine have been used for pain management. There are concerns related to the use of codeine for this purpose, particularly regarding the potential for neonatal toxicity and opioid-related adverse events for the postpartum patient. There is limited evidence regarding the clinical effectiveness of codeine, with or without acetaminophen or nonsteroidal anti-inflammatory drugs, in patients who have undergone Caesarean section. One randomized controlled trial found that codeine in combination with paracetamol (i.e., acetaminophen) provided better pain relief compared to paracetamol only or placebo in patients with high levels of post-Caesarean section pain. However, no difference in pain relief was observed between codeine in combination with paracetamol, paracetamol only, or placebo in patients with moderate levels of post-Caesarean section pain. No evidence was found regarding the clinical effectiveness of codeine alone for acute pain in this specific population.