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Background Cancer pain that cannot be adequately controlled despite optimal treatment presents a significant challenge in palliative care. Ketamine has been proposed as an adjunct to address this but the evidence base is inconclusive. In particular, its efficacy, tolerability and safety profile have been debated.Aim To review and critically appraise the use of ketamine for refractory cancer pain in palliative care. The aim is to synthesise the current evidence, identify knowledge gaps and inform clinical practice in the future.Methods We conducted a narrative literature review using PubMed, Embase and Cochrane databases. Inclusion criteria encompassed studies published between 2000 and 2025; those that analysed the use of ketamine in adults with cancer-related pain that was inadequately controlled with standard opioid therapy. Furthermore, quantitative and qualitative data were considered – this included clinical trials, observational studies and case series.Results The literature suggests that ketamine may offer analgesic benefit in some patients with refractory cancer pain. Indeed, several studies reported reduced pain scores and opioid-sparing effects. However, evidence from randomised control trials is limited and often of poor quality. Adverse side effects, such as hallucinations and agitation are reported with irregular frequency. Higher-level evidence, such as guidelines or meta-anlayses are cautious on this topic, often advocating for further research.Conclusion High quality evidence is lacking for using ketamine to address refractory cancer pain in palliative care. Despite this, it still remains a promising option but its use should be guided with specialist input and careful patient selection. In order for this to be used more widely, further robust clinical trials are required. This review highlights the importance of evidence-based decision-making and supports the development of consensus guidelines for ketamine use in palliative settings.