RT Journal Article SR Electronic T1 Low-dose naltrexone as a treatment for chronic fatigue syndrome JF BMJ Case Reports JO BMJ Case Reports FD BMJ Publishing Group Ltd SP e232502 DO 10.1136/bcr-2019-232502 VO 13 IS 1 A1 Bolton, Monica Jane A1 Chapman, Bryan Paul A1 Van Marwijk, Harm YR 2020 UL http://casereports.bmj.com/content/13/1/e232502.abstract AB Naltrexone is used as an off-label treatment in low doses for several chronic immune-modulated disorders in many countries. Although only small-scale clinical trials have been performed, these suggest efficacy in several diseases including Crohn’s disease, fibromyalgia and Gulf War Illness. Despite numerous internet reports of response to low-dose naltrexone (LDN), no clinical trials exist in people with chronic fatigue syndrome. This condition is characterised by chronic profound fatigue, postexertional malaise, pain and autonomic and neurocognitive disturbances. This series of three case reports compiled by people with long-term ill-health due to chronic fatigue syndrome shows the range of responses they observed when taking LDN, from life changing to a reduction in some symptoms only. Treatment doses ranged from 4 to 12 mg. Clinical trials may be warranted to explore the potential use of naltrexone in people with these debilitating illnesses which currently have no licensed treatments available.