Reg Anesth Pain Med

Standardized ketamine infusion shows promise for chronic refractory pain

October 16, 2025

Given its high treatment adherence and sustained symptom relief, ketamine may be a viable non-opioid option for patients who have exhausted conventional therapies for chronic refractory pain. Further prospective studies are needed to refine protocols and identify optimal candidates for treatment.

Study details: This retrospective observational study included 1,034 adults with chronic refractory pain treated at a multidisciplinary outpatient pain clinic using a standardized ketamine infusion protocol (0.5 mg/kg over 40 minutes, daily for five days). Effectiveness was assessed via patient-reported outcomes (PROs) at baseline, post-treatment, and at 3- and 6-month follow-up.

Results: Treatment completion was high (86.1%), with no serious adverse events reported. Between 20.3% and 46.4% of patients achieved clinically meaningful improvement in PROs at the end of treatment, with similar proportions at 3 and 6 months. Statistically significant mean improvements were observed in fatigue, pain interference, and social role satisfaction, and these gains were sustained through 6 months. Most individual outcomes didn't reach clinically meaningful thresholds, but group-level improvements were consistent.

Source:

Tankha H, et al. (2025, October 5). Reg Anesth Pain Med. Standardized ketamine infusion protocol for chronic refractory pain: a retrospective study of preliminary effectiveness and treatment completion. https://pubmed.ncbi.nlm.nih.gov/41047247/