Efficacy and practicality of codeine

Thank you for bringing this important issue to the attention of CMAJ’s readership.1 As clinicians, we all wish to deliver evidence-based and effective pain treatment to our patients by considering efficacy, safety and practicality. The editorial focused on safety; we’d like to highlight the limitations of codeine in the other areas.

Clinical trials have demonstrated repeatedly that codeine is no more effective than ibuprofen in providing relief of mild to moderate pain.2^–4 In many trials, the number of side effects reported by patients receiving codeine was substantially higher than those reported by patients receiving ibuprofen.2^–4 These adverse effects, reported by 50% to 71% of the patients, likely affect compliance. In addition, the poor palatability of codeine suspension is an issue in children, who rated this aspect of their experience with codeine as highly unsatisfactory.3

Given the well-recognized negative side-effect profile for codeine, can we justify choosing a drug that will likely be avoided by the patient in clinical scenarios where ibuprofen has a comparable clinical effect with a more favourable profile?

We cannot ignore the real safety concern associated with genetic differences in metabolism of codeine for a subsection of the population. However, clinical trials also suggest that codeine is no more effective than ibuprofen, and there are several drawbacks that likely affect compliance and effectiveness. Because there are alternative analgesics (e.g., ibuprofen) and opioids (e.g., hydrocodone and oxycodone) available with efficacy and safety profiles superior to that of codeine, we advocate for their thoughtful/judicious use over codeine.