Ketamine Safe, Effective for Chronic Pain
Low-dose ketamine infusions are both safe and significantly effective for patients with chronic pain, according to one of the largest real-world studies of its kind published in Regional Anesthesia & Pain Medicine. Led by researchers at Cleveland Clinic's Neurological and Primary Care Institutes, the study analyzed data from over 1,000 patients, providing crucial evidence for this emerging treatment approach.
"We know millions of Americans are suffering from chronic pain and this research addresses critical gaps in pain management and shows a significant step forward in improving care for those patients who have otherwise exhausted all other treatment options," said Pavan Tankha, D.O., medical director of Comprehensive Pain Recovery in Cleveland Clinic's Neurological Institute. "The findings of the research represent a meaningful step toward improved quality of life and may accelerate access to this treatment option for patients all over the country."
Notable Improvements Reported
The retrospective study followed 1,034 patients through a standardized ketamine infusion protocol – 0.5 mg/kg over 40 minutes for five consecutive days – and demonstrated an 86.1 percent adherence rate, underscoring the feasibility of outpatient administration.
The outpatient ketamine protocol demonstrated strong feasibility, with over 90 percent of patients completing all five treatment days. Outcomes were measured using the NIH's PROMIS tool, which assesses physical, mental, and social health. Patients reported notable improvements in pain symptoms and quality of life.
The ketamine protocol, delivered within a comprehensive clinical pain program, helped 20 percent to 46 percent of patients achieve meaningful improvements in their daily functioning, sleep, and pain management. Additionally, 80 percent of patients returned for repeat infusions, demonstrating sustained benefit and patient treatment satisfaction.
Life-Changing Ketamine Infusions
"This study provides evidence for ketamine's role in chronic pain management," said Hallie Tankha, Ph.D., a clinical pain psychologist in Cleveland Clinic's Primary Care Institute and co-investigator of the study. "This is in line with my clinical experience as a pain psychologist, as patients often describe ketamine infusions as 'life changing'. I'm encouraged by treatments that can be integrated into comprehensive care approaches, and this study demonstrates ketamine can be safely and effectively implemented in pain management settings."
Patients were followed for over six months, providing long-term evidence of sustained benefit. Data showed improvements in pain interference, depression, and physical function lasting up to six months, with nearly half of patients showing clinically meaningful improvement in pain-related anxiety.
The research demonstrated that low-dose ketamine was safe, with minimal side effects. Hallucinations, the most reported side effect, were rare. No serious adverse events were reported across the entire cohort. Key advantages of low-dose ketamine include low tolerance risk, feasibility of outpatient administration, and no requirement for anesthesia.
Hope for Those With Chronic Pain
According to the study's authors, this research highlights the importance of integrating ketamine therapy within a comprehensive pain program, combining infusions with behavioral therapies and patient education.
The findings lay the groundwork for larger controlled trials and adoption in multidisciplinary pain centers. This study offers hope for those living with chronic pain who have not responded to conventional treatments.
Ketamine is currently used off label for pain, underscoring the importance of research like this to support FDA approval and broader hospital availability.
Source: Tankha, H., et al. "Standardized ketamine infusion protocol for chronic refractory pain: a retrospective study of preliminary effectiveness and treatment completion." Regional Anesthesia & Pain Medicine 5 October 2025.