In higher doses, Naltrexone is used largely in the treatment of alcohol and opioid dependency. However, in much lower does – typically just one tenth of the high-dose strength – Naltrexone has been touted as a panacea in the treatment of a host of autoimmune and other conditions. But, there remains a lack of credible clinical evidence as to its efficacy.
In one review, the authors reported:
“Fewer studies support the efficacy of low-dose naltrexone, with most of these focusing on subjective measures such as quality of life or self-reported pain. These studies do demonstrate that low-dose naltrexone has subjective benefits over placebo, but evidence for more objective measures is limited.”
What is the science?
Traditionally it was thought that pain signals were transmitted through and affected solely by neurons. However, some years ago it was discovered that non-neuronal cells in the spinal cord called neuroglia or glia, actually amplify pain when they receive certain signals from the peripheral nervous system. It is thought that Naltrexone may act to reduce the effect of the glia in amplifying pain.
In 2013, the Journal of Neuroimmune Pharmacology reported the cases of two people with seemingly therapy-resistant CRPS who were prescribed low dose Naltrexone in addition to their regular medication. One of them reported a significant and sustained improvement in their symptoms, while the other seems to have achieved complete remission. In both cases no side effects were reported.
It has been hypothesised that low-dose Naltrexone may be effective in the treatment of CRPS as the condition involves both central sensitisation of the central nervous system and activation of the glia.
Subsequently, in 2017, we reported that Stanford University were recruiting participants for a large clinical trial of low-dose Naltrexone in the treatment of CRPS. With the passing of over two years, have the researchers reached any conclusions?
It seems not. The trial continues and according to their website they are still “currently accepting patients for this trial.”
While it is not possible to predict the outcome, the continuance of this trial does suggest that there have been no significant doubts regarding its efficacy, safety or feasibility. Clearly, the longer it continues and the greater number of participants recruited, the more accurate the results are likely to be.
Watch this space.