Cree 2010: low-dose naltrexone and quality of life in MS

What they tested

People with multiple sclerosis, a disease in which the immune system damages nerves, took low-dose naltrexone (LDN) 4.5 mg each night for 8 weeks and a placebo (dummy pill) for 8 weeks. In a crossover design like this, each person serves as their own comparison. Neither participants nor staff knew which period was which.

The outcome was self-reported quality of life, measured with several standard questionnaires.

What they found

On LDN, scores improved by 3.3 points on the SF-36 Mental Component Summary (p = 0.04), 6 points on the Mental Health Inventory (p < 0.01), 1.6 points on the Pain Effects Scale (p = .04) and 2.4 points on the Perceived Deficits Questionnaire (p = 0.05).

LDN was well tolerated, and there were no serious adverse events.

Ten people withdrew before finishing the first period: 8 for personal reasons, 1 for an adverse event unrelated to MS and 1 because they felt they had already benefited. Data errors affected 4 more people, and 6 had incomplete surveys for unknown reasons.

Limits

• Dropouts and data management errors substantially reduced the trial's statistical power, according to the authors.
• Each treatment period lasted 8 weeks, at a single center.
• It measured quality of life only, not whether MS itself progressed more slowly.

What it means if you're considering naltrexone

Low-dose naltrexone is a different use from the 50 mg tablet used for alcohol or opioids. This pilot found better mental-health quality-of-life scores on LDN in people with MS, and no serious side effects, but it lost a quarter of its participants.

A second trial in MS the same year found no meaningful differences, so the evidence is mixed. The authors called for further studies.