Long covid has been a descriptor that many will be familiar with. From brain fog to chronic fatigue to general discomfort and even pain; there are many different symptoms individuals have experienced and have likely hoped for treatment of.
Recent research has investigated the pharmaceutical role of Naltrexone, an opioid antagonist medication, used traditionally for the treatment of alcohol and opioid substance abuse patients, in possibly relieving the load of long covid.
Byambasuren O, et al, (2026) performed a systematic review and meta-analysis into the effect of low dose-naltrexone (LDN) on these symptoms through its known influence on inflammation on immune system activity. The study analysed 397 different relevant studies, in which no random-controlled trials were identified, however, four observational pre-post studies from the USA and Ireland were found. Within the studies it was found “low does” varied from 1mg to 6mg/day, with the pre-post effect posting a subjective moderate decrease in fatigue for those involved. Additionally, sleep quality improved and large improvements for chronic pain and daily function.
However, it is pivotal to understand that there no RCTs involved and the researchers themselves cannot confidently determine whether the improvements were directly caused by LDN or rather natural recovery or other treatments.
What will be required is further research isolating in LDN within a RCT to really determine its effects, so whilst this study is a glimmer into possibility there still a lot to uncover for the future of long covid.
Source: Byambasuren, O., Atkins, T., Baptista, S., Glasziou, P., & Chakraborty, S. (2026). Effect of low-dose naltrexone for long COVID: a systematic review and meta-analysis. BMJ open, 16(7), e111253. https://doi.org/10.1136/bmjopen-2025-111253
