Opioid-refractory rectal tenesmus treated with burst ketamine.
David Murphy, Hannah O'Brien, Mary Jane O'Leary
BMJ Supportive & Palliative Care June 26, 2025 DOI: 10.1136/spcare-2025-005552 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case study Case report Peer reviewed |
|---|---|
| Sample size | 1 |
| Population | A man with difficult-to-manage rectal tenesmus caused by rectal carcinoma |
| Interventions | Ketamine Midazolam Dexamethasone |
| Duration | Seven days |
| Topics | Esketamine Ketamine |
| Keywords | Cancer Gastrointestinal lower Palliative care Severe rectal tenesmus Opioid-resistant rectal tenesmus Intense discomfort Lower gastrointestinal pain Novel approach |
| Citations | 1 |
| Key findings | A seven-day continuous subcutaneous infusion of ketamine, combined with midazolam and dexamethasone, decreased pain and opioid requirements in a man with rectal tenesmus. |
Abstract
Rectal tenesmus is the painful sensation of incomplete evacuation of the bowels, which is distressing and difficult to manage. Tenesmus is often caused by rectal carcinoma. It is thought there is a significant neuropathic component to tenesmus pain. Ketamine is an antagonist to the N-methyl D-aspartate receptor and has been used for neuropathic pain. We describe the case of a man with difficult-to-manage rectal tenesmus who experienced adverse effects to several medications, limiting titration. A trial of 'burst' ketamine over seven days via a continuous subcutaneous infusion, combined with midazolam and dexamethasone, resulted in a decrease in his pain, as shown by his improved self-reported pain scores and reduced PRN and background opioid requirements. To the authors' knowledge, this is the first report of using ketamine for rectal tenesmus.
Comparable studies
Other case reports and case series on ketamine, most cited first.