Many people are unfamiliar with the use of low dose naltrexone (LDN) other than as regular dosed naltrexone which is used to support individuals with addiction recovery. However, at much lower doses it can be useful for people with ME/CFS, Long COVID, mast cell activation syndrome, fibromyalgia, chronic pain and other conditions.
At doses from 0.1mg – 7 mg, LDN it helps to fight pain and reduce inflammation. It works by binding to opioid receptors for just a couple of hours which stimulates the body to create more receptors and increase endorphin levels. Endorphins have pain relieving and mood boosting effects. In addition, it is an anti-inflammatory reducing the production of cytokines, including those causing neuroinflammation.
Neuroinflammation is associated with brain fog. I reach for this tool often when treating my patients. There is no drug that helps everyone, and response varies, but in general many of my patients have had good responses with decreased pain, fatigue and brain fog. It can take 2-3 months to see the full effects. I would say that roughly 75% of my patients have enough improvement to want to continue taking it. Dosing is personalized and there is a process to find the best dose for each individual.
- Potential benefits: LDN can help reduce neuro-inflammation, improve pain perception, and even regulate the immune system.
- When do I use it? I think about this tool in my patients with fatigue, pain, brain fog and mast cell activation syndrome (yes, this is most of my patients!)
Important Things to Keep in Mind:
- Find the right dose: You’ll want to work closely with a doctor to find the right dose of LDN for your patient-specific case. Start low, go slow!
- Possible side effects: Some people may experience mild side effects like nausea, insomnia, or vivid dreams. Often, these side effects are temporary and go away with time. Some patients take LDN during the morning hours to lessen the impact on sleep.
- Where to Learn More: For more information about LDN, including its potential benefits and risks, check out our informational handout.

Lucinda Bateman, MD, is a renowned clinician, researcher, and educator. Her Johns Hopkins University Medical School training instilled an approach to care that she has employed throughout her career – the patient comes first and the unknown or unexplained does not equate to a lack of proper and compassionate care. Since starting her own practice in 2000, she has served on six boards or committees, been the principal investigator for 45 studies, authored/coauthored 40 journal articles, served as adjunct instructor and adjunct assistant professor in the University of Utah Departments of Preventative Medicine, Internal Medicine, and Anesthesiology, and lectured around the world.