Evidence Hub

Low dose naltrexone for fibromyalgia: case series demonstrating pain relief and other health benefits

Junek A, Anderson M

Frontiers in pain research (Lausanne, Switzerland), 2026

10 participants

Abstract

Fibromyalgia is a chronic pain disorder with multiple proposed etiologies. Pharmacological treatments approved for fibromyalgia are few and not always effective; therefore, some practitioners use off-label medications such as low dose naltrexone (LDN). This case series presents a retrospective chart review of patients who were prescribed LDN for fibromyalgia at an integrative medicine clinic over a 2-year period. Outcomes assessed included pain relief, other health benefits, side effects and prescription habits. Of 10 patients identified, LDN provided substantial pain relief for 8 patients (-4.7/10 points, average -3.75/10 for all 10 patients, p < 0.001). These same patients also reported other important health benefits such better quality of life in 6 patients, reductions in pain flares in 5 patients, improved sleep in 4 patients, improved cognitive functioning in 2 patients, and cessation of other pain medications in 4 patients. Two patients discontinued LDN due to side effects, which in both cases was increased pain. LDN was well tolerated overall, although reported side effects included increased pain, vivid dreams, insomnia and irritability. LDN's proposed mechanism involving hormesis at opioid receptors and its implications for customized dosing in clinical care and research trials are discussed. While not all patients respond to LDN, this medication shows promise as an effective and safe intervention and deserves to be considered as a treatment recommendation for…

How strong is the evidence?

Evidence Hub reads this as a case series, done in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health. Reported size: 10 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free