Peptide Knowledge Base · Immune
Low-Dose Naltrexone (LDN): what it is, what the evidence says, and its real status
An off-label low dose of an approved drug, not a peptide, used for immune and inflammatory conditions.
Short version: not a peptide, a low dose of the approved drug naltrexone, used off-label for pain and autoimmune symptoms. Education only here.
Can you actually get it?
Plain-English verdict: Education only.
Regulatory status: Education only · Education only.
Not offered on the peptide surface, education only. LDN is a low dose of the FDA-approved drug naltrexone, used off-label for autoimmune and chronic-pain symptoms. It is a related compound, not a peptide.
How does Low-Dose Naltrexone (LDN) work?
At low doses, transient opioid-receptor blockade is proposed to modulate immune signaling and microglial activity.
What it does — and what it does not do
What it does: Studied for autoimmune-related symptoms, chronic pain, and inflammation.
What it does not do: Evidence is limited to small studies, it is not a peptide, and it is not offered on this surface.
How honest is the evidence?
Evidence grade C — small human studies in autoimmune/pain contexts; larger trials lacking. Read our grading methodology for what each grade means.
What we still don't know: Large randomized trials are lacking; effect sizes vary by condition.
WADA status: Not prohibited.
How it is taken
Not offered; education only.
Who should not take it
Not for those on opioid therapy; clinician oversight for autoimmune contexts.
Sources
Low-dose naltrexone immune/pain pilot studies
Compounded medications are not FDA-approved. We keep two signals separate and never collapse them: whether you can get something, and what the rule currently says. See the live FDA Peptide Tracker or the knowledge base.
Last reviewed 2026-08-11 · Peptós.LIFE · Not medical advice.