IMAGE DESCRIPTION: A pink background an image of a a pink pill with the empty foil packaging to represent Low-Dose Naltrexone. The title reads: Low-Dose Naltrexone Could Treat Long COVID Symptoms. The ME Association logo (bottom right)

Low-Dose Naltrexone Could Treat Long Covid Symptoms

Low-dose naltrexone may be a promising treatment for long COVID, but more studies are needed.

By Stephanie Brown

Very Well Health has an article about Low-does naltrexone (LDN) and Long Covid that highlights the research study “A double blind randomized trial of low-dose naltrexone for post-covid fatigue syndrome” that has received funding through the Canadian Institutes of Health Research.

Dr. Luis Nacul (Co-Principal Investigator at the ME/CFS UK Biobank) and colleagues plan to undertake this research in 2023/24 and the press release from March 2023 said: “Findings from this study stand to benefit people who experience ‘Post-covid fatigue syndrome’ (PCFS) lend support for further studies on the use of low dose naltrexone for post-viral fatigue syndrome and ME/CFS.”


Naltrexone is a drug approved by the Food and Drug Administration (FDA) to treat alcohol use disorder and opioid addiction. Low-does naltrexone (LDN), usually at a fraction of the regular dose, has been used to treat fibromyalgia and multiple sclerosis.

While LDN might not cure all long COVID symptoms, it could serve as part of a treatment plan. A small study published last year found that LDN improved some self-reported symptoms, such as pain and energy levels, for long COVID patients.

It looks like it worked for most people. So I think it’s part of the solution because it’s targeting two of the four issues that I see really critical with long COVID, which is brain inflammation and immune dysregulation.

Jack Lambert, MD, PhD, a co-author of the study and a professor of infectious disease at the University College Dublin School of Medicine in Ireland.

When LDN is prescribed, Bender explained, people often start with a very low dose and work their way up to a higher dose. While people might see improvements after a few weeks, she said it is difficult to track how well the drug works because it’s often prescribed along with multiple treatments.

Clinical trials are still needed to help healthcare providers understand exactly how this LDN works. A placebo-controlled study in British Columbia looking at the effects of LDN on long COVID fatigue may be underway soon, which could help provide some answers.

ME Association comment

Dr Charles Shepherd, Honorary Medical Adviser to the ME Association provides the following information:

Key points on the use of Low-Dose naltrexone (LDN)

  • At normal doses, naltrexone is a drug that is used to treat alcohol and opiate addiction.
  • At lower doses (ie low dose naltrexone) it is being used by people with a wide range of medical conditions – including ME/CFS, fibromyalgia, inflammatory bowel disease, and multiple sclerosis.
  • There are a number of reasons (eg reducing cytokine-mediated inflammation) why it might be effective in such a wide range of conditions. But these remain speculative and are not yet proven.
  • In the absence of any evidence of safety and efficacy from well conducted clinical trials, LDN remains a speculative form of treatment. Consequently, LDN does not have a product license or NICE recommendation for any of these conditions and NHS doctors are reluctant or refuse to prescribe it.
  • Clinical trials are now taking place and the results, especially those from the trial that Dr Luis Nacul and colleagues are doing, should provide us with some more solid evidence as to whether LDN is a potentially useful treatment for Long Covid or ME/CFS.
  • Feedback to the ME Association from people with ME/CFS who have used LDN is very mixed. So in our current state of knowledge, this is not a drug that we can recommend.

Dr Charles Shepherd,
Trustee and
Hon. Medical Adviser
to the ME Association.

Dr Charles Shepherd
Shopping Basket