Ketamine for Fibromyalgia: Sustained Relief for Two Years

Psiconáutica Editorial Team · September 4, 2026

A team at the Carolinas Pain Institute in Winston-Salem has reviewed the medical records of 92 women with severe fibromyalgia treated with repeated ketamine infusions over a six-year period. According to the authors, this is the most extensive retrospective analysis published to date on this long-term therapy—a gap left by previous studies, which were almost all limited to fewer than 35 participants and lacked long-term follow-up.

How it was done

The patients, aged 24 to 78, received intravenous ketamine sessions of 300 to 500 mg over approximately three hours, repeated when pain levels rose again, with a typical interval of six months (ranging from three to ten months depending on the case). The protocol included midazolam before the infusion to reduce hallucinations, and ondansetron plus promethazine for nausea. One-third of the patients were taking opioids at the start of treatment. The study, reviewed by a hospital ethics committee, is observational: there is no comparison group or randomization, so it demonstrates a correlation in real-world clinical practice rather than a causal proof in the strict sense. It does, however, align with research suggesting that ketamine relieves pain through a pathway distinct from dissociation.

What the data shows

Average pain, measured on a scale of 0 to 10, dropped from 8 at baseline to 5 at three months, remaining quite stable there until 24 months. At three months, 32 of the 92 patients reported more than 50% less pain; at two years, that level was maintained by 30 patients. Including more modest improvements, 58% noted at least 30% relief at 24 months, and 75% reached what the authors consider a clinically relevant improvement. Nineteen patients, however, noticed little difference. Regarding adverse effects, there were reports of nausea (12 cases), hallucinations (10), vomiting (3), confusion (1), and nightmares following the session (2); none were severe, and there were no signs of the liver or bladder damage described with continuous ketamine infusions maintained over several days. The number of patients using opioids dropped from 33 to 27, although the average dose among those who continued taking them did not change.

What it implies

The authors themselves highlight the limitations: it is a single-center study without a control group, and during the two years of follow-up, many patients also changed other treatments (antidepressants, muscle relaxants, anti-inflammatories), making it difficult to isolate how much relief is attributable solely to ketamine. There is also no standard protocol for dosage or intervals between clinics; in this study, experience led to lowering doses over time because 300 mg provided similar relief to 500 mg with fewer hallucinations. That said, the interesting finding is not so much the response rate—which is similar to smaller previous studies—but the duration: some patients have been repeating infusions for more than two years with a consistent response pattern, with no signs of the effect wearing off with repeated use or severe cumulative toxicity. The authors are now calling for a larger randomized trial to confirm these results. For those already using ketamine in a clinical or non-clinical context, with harm reduction as a priority, the relevant takeaway is the premedication: midazolam before the infusion and antiemetics alongside the ketamine significantly reduce hallucinations and nausea, two of the effects that most limit tolerability.

Source

• Kapural L, Choi S, Rogers EJ, Viradia I, Bekavac B. A Single-Day Intravenous Ketamine Infusions for Fibromyalgia, a Large Retrospective Study with a Long-Term Assessment. Journal of Pain Research, August 19, 2026.

Educational content written from a harm reduction perspective and with respect for individual freedom. It is not a substitute for advice from a healthcare professional and is not intended to encourage or condemn any drug use.