Naltrexone, which reverses the effects of opiates like morphine or heroin, is one of the more controversial but poorly studied potential therapies for MS.

It is used in clinical practice in people trying to recover from opiate addiction.

How low-dose naltrexone (LDN) works in multiple sclerosis and other immune-mediated diseases, if it does, is the subject of conjecture.

But there seems to be overwhelming anecdotal evidence that it prevents relapses and reduces disease progression.

It may act by reducing cell death in oligodendrocytes (the myelinating cells of the central nervous system).

Evidence of its apparent benefit in individual cases has been published on a number of websites, but to date, there are no results from randomized controlled trials, although several are in progress.

Low-Dose Naltrexone infographic

Benefits of Low Dose Naltrexone

  • It is relatively free of side effects, unlike many heavily promoted immune-modulating therapies
  • It is a generic drug that cannot be patented, so it is far cheaper than other currently available drugs – which may explain why it hasn’t been studied much

Among recent treatment trials

After two-thirds of patients with Crohn’s Disease went into remission and 89% responded to LDN in a pilot study, researchers at Penn State University studied 40 people with Crohn’s Disease in a RCT.

Patients received naltrexone or placebo for 12 weeks; all received naltrexone for another 12 weeks.

  • After 12 weeks: 88% of those receiving LDN showed a 70-point decline in Crohn’s Disease Activity Index scores, compared to just 40% of those receiving placebo
  • After 12 more weeks: 50% of patients who had received LDN from the start went into remission (scores declined another 75 points), while 70% of those who had previously received placebo showed a 70-point decline in CDAI scores

LDN MS research is underway. One LDN MS treatment RCT at the University of California enrolled 80 patients with relapsing-remitting MS.

The researchers found significant improvements for LDN over placebo in several mental health quality of life measures.

Another study of short duration (only 17 weeks) enrolled 96 PwMS, however found no difference over placebo in measures of quality of life.

More info can be found on the LDN Research Trust website. 


1. Agrawal YP. Low dose naltrexone therapy in multiple sclerosis. Med Hypotheses 2005; 64:721-724
2. Smith JP, Stock H, Bingaman S, et al. Low-dose naltrexone therapy improves active Crohn’s disease. Am J Gastroenterol 2007; 102:820-828
3. Cree BA, Kornyeyeva E, Goodin DS. Pilot trial of low-dose naltrexone and quality of life in multiple sclerosis. Ann Neurol 2010;68:145-50
4. Sharafaddinzadeh N, Moghtaderi A, Kashipazha D, Majdinasab N, Shalbafan B. The effect of low-dose naltrexone on quality of life of patients with multiple sclerosis: a randomized placebo-controlled trial. MultScler 2010;16:964-9