Tsui 2024: low-dose naltrexone for pain in people with HIV who drink

What they tested

In 2021, researchers in St. Petersburg, Russia, randomly assigned 45 people with HIV to one of three daily treatments: low-dose naltrexone 4.5 mg, gabapentin (up to 1800 mg), or a placebo, a dummy pill. There were 15 people in each group, and neither they nor the researchers knew who got what.

The two main outcomes were changes in pain severity and in how much pain interfered with daily life, both measured with the Brief Pain Inventory, a standard questionnaire, from the start to week 8.

What they found

At the start, 64% were men, the average age was 41, and people reported a mean of 2 heavy drinking days in the past month. Average scores were 3.2 for pain severity and 3.0 for pain interference.

Pain severity fell in all three groups, including placebo. Compared with placebo, the difference in the change in pain severity was 0.88 for low-dose naltrexone (95% confidence interval -0.7 to 2.46; p = 0.55) and -0.27 for gabapentin (p = 0.73). Neither difference was statistically significant.

Pain interference also fell in all three groups. The differences from placebo were 0.40 for low-dose naltrexone and 0.16 for gabapentin, both with p = 0.83, so neither drug showed a clear effect.

Limits

• It was a pilot trial with 15 people per group, too small to rule out a modest effect.
• Everyone had HIV and was recruited in one city in Russia, so the results may not apply to other groups.
• The trial lasted 8 weeks, and its main questions were about pain, not drinking.

What it means if you're considering naltrexone

Low-dose naltrexone is a small fraction of the usual naltrexone dose and is not a treatment for alcohol use disorder. This small trial adds to other placebo-controlled studies that found no clear pain benefit from it, and it offers no support for using it in place of standard alcohol treatment.