Low-Dose Naltrexone for Fibromyalgia: What the Research Actually Shows
Jarred Younger, PhD, directs the Neuroinflammation, Pain and Fatigue Laboratory at UAB and ran two of the earliest clinical trials testing low-dose naltrexone (LDN) for fibromyalgia pain, both showing a reduction versus placebo. Since then, a larger, independent randomised trial (the 2024 Lancet Rheumatology FINAL trial) failed to beat placebo. Both results are real and stated here together, not just the promising one. LDN is a prescription medication; every dose is individually compounded, and it must be prescribed and monitored by a clinician, never self-started.
LDN is proposed to work by calming microglial neuroinflammation rather than through classic opioid-receptor blockade n/a, education only
This is the biological rationale behind why a drug normally used at higher doses for addiction is being trialed at a much lower dose for pain.
Younger's own small pilot trials found a pain reduction versus placebo; the larger, independent FINAL trial (Lancet Rheumatology, 2024) found no significant benefit over placebo n/a
An honest picture includes the disputed, larger negative trial alongside the smaller positive pilot data, not just the result that supports the hypothesis.
LDN requires a prescriber, every low dose is individually compounded by a pharmacy, and typical trial doses were around 4.5mg/day n/a, physician-prescribed and monitored
Naltrexone blocks opioid painkillers and interacts with other medications, so dosing and monitoring belong to a prescriber who knows your full medication list.
Naltrexone is normally prescribed at higher doses to block opioid receptors for addiction treatment.
View sources
Scientist Dr Jarred Younger talks about Low Dose Naltrexone
Fibromyalgia Podcast, Episode 21: Cutting-Edge Fibromyalgia Research with Dr. Jarred Younger
Low-Dose Naltrexone Researcher Disputes Fibromyalgia Study Negativity
Fibromyalgia Symptoms Are Reduced by Low-Dose Naltrexone: A Pilot Study
Not medical advice. This page is for education only and is not a substitute for professional medical care. Consult a qualified clinician before changing your health routine.
Independent curation. YourProtocol is an independent platform. This protocol is based on the publicly available work of Jarred Younger, PhD and is not created, reviewed, endorsed by, or affiliated with Jarred Younger, PhD or University of Alabama at Birmingham.
Is this for you
- People with fibromyalgia curious about LDN who want both sides of the evidence
- Anyone whose doctor has mentioned LDN and wants the mechanism explained plainly
Cautions
- This is mechanism and evidence education, not a self-directed treatment
- A larger, independent trial found no benefit over placebo; results are genuinely mixed
- Naltrexone is prescription-only; never self-start or self-source it