Three PubMed abstracts report low-dose naltrexone (LDN) in people with multiple sclerosis (MS), and their reported results differ. An 8-week crossover pilot of 4.5mg nightly reported a 3.3-point improvement on a mental health quality-of-life score, but its authors said dropout and data management errors substantially reduced the trial's statistical power. A 17-week randomized trial in 96 adults reported no meaningful statistical difference between groups in most quality-of-life variables.
The three studies at a glance
All three sources are PubMed abstracts, so this guide goes only as far as the abstracts do. In a crossover design, each person takes both the study drug and the placebo, one after the other. "Double-masked" and "double-blind" mean that neither participants nor researchers knew who was taking which.
| Study | Dose and design | Size |
|---|---|---|
| Pilot trial, Annals of Neurology, 2010 | 4.5mg nightly naltrexone for 8 weeks. Single-center, double-masked, placebo-controlled, crossover. | 80 enrolled, 60 completed |
| Randomized trial, Multiple Sclerosis Journal, 2010 | Dose not stated in the abstract. Randomized, double-blind, placebo-controlled, crossover design, 17 weeks. | 96 adults with relapsing-remitting or secondary progressive MS |
| Pilot trial, Multiple Sclerosis Journal, 2008 | Dose not stated in the abstract. Pilot trial; this source is classed as observational. | 40 patients with primary progressive MS |
What each study measured and reported
The 8-week pilot evaluated the effect of nightly naltrexone on the self-reported quality of life of people with MS. It reported that LDN was associated with significant improvement on mental health quality-of-life measures, including a 3.3-point improvement on the Mental Component Summary score of the Short Form-36 General Health Survey (p = 0.04).
The 17-week randomized trial also looked at quality of life. Variables including presence of pain, energy, emotional well-being, social, cognitive and sexual functions, role limitation due to physical and emotional problems, health distress and overall quality of life did not show any meaningful statistical difference between the two groups.
The 2008 pilot reported five dropouts and two major adverse events. It also reported a significant reduction of spasticity measured at the end of the trial. Because it is classed as observational, it cannot show that the drug caused that change.
Dropouts, tolerability and the authors' own limits
In the 8-week pilot, 80 people were enrolled and 60 completed. The authors state that the high rate of subject dropout and data management errors substantially reduced the trial's statistical power. That limit belongs next to the 3.3-point result (p = 0.04) and should be read with it. The authors also state that LDN was well tolerated and that serious adverse events did not occur in that trial. A statement that a drug was well tolerated in one small trial does not mean that no one had side effects.
In the 2008 pilot, the abstract says the remaining adverse events did not interfere with daily living. The part of the 17-week trial's abstract summarized here does not give the dose and does not report adverse events.
What this does not tell you
These abstracts do not establish benefit of LDN for any person with MS, and they do not show that a result would apply to a particular person. Two of the three report quality-of-life measures and reached different results, with different lengths and sizes, so they cannot be added together. Two abstracts do not state the dose. The 2008 pilot is observational. Newer studies may exist that this guide does not cover.
A licensed provider reviews each person's situation and decides whether LDN is suitable. This guide cannot say that.