Researchers are also looking at its effectiveness in treating multiple sclerosis, Crohn’s disease, and long COVID.

More recently, researchers found low doses of naltrexoneabout 1/30th the standard dosemay be useful for other conditions.

This article discusses low-dose naltrexone benefits and uses related to fibromyalgia, chronic fatigue syndrome, and other conditions.

Medication being poured into hand.

Jack Hollingsworth / Getty Images

It also explains the side effects of LDN therapy and what to avoid when taking naltrexone.

How Does Low-Dose Naltrexone Work?

Here is a closer look at low-dose naltrexone benefits and uses.

LDN is not FDA-approved for fibromyalgia but is sometimes prescribed for off-label use.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is also known asmyalgic encephalomyelitis.

Every person with chronic fatigue syndrome has a unique set of symptoms and degree of intensity.

LDN is sometimes prescribed off-label for chronic fatigue syndrome.

There is growing evidence that some individuals have seen a reduction in their symptoms while using LDN.

This can cause pain, muscle weakness, fatigue, and cognitive problems.

A few studies have looked at LDN as a treatment for patients with long COVID.

It does appear to be safe and well-tolerated for people with Crohn’s.

Cancer

LDN has also been studied for its anticancer properties.

However, studies that have found efficacy against certain cancers have largely been limited to animal models.

Animal studies do not always translate well to human beings.

More research is needed before LDN can be recommended as a treatment for people with cancer.

How long does it take for low dose naltrexone to work?

The time it takes for low-dose naltrexone to become effective varies from person to person.

Research shows that the drug seems safe for long-term use.

As long as naltrexone benefits you, it’s possible for you to take it on an ongoing basis.

Long-term side effects are uncommon with low-dose naltrexone.

These tend to occur more often at higher doses.

Contact your healthcare provider right away if you experience any of these.

People withkidney diseaseorliver diseasemay need to speak with their doctor before starting LDN.

Those who are pregnant or breastfeeding should also speak with their doctor before starting this medication.

Interactions

You should avoid alcohol and certain other drugs when taking low-dose naltrexone.

Cytochrome P450 (CYP450) is a protein that helps your body metabolize drugs.

In research and case studies, LDN has been shown to help decrease symptoms with minimal side effects.

However, most of these studies have been small and more research is needed.

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