Naltrexone is one molecule living two very different lives. At the full tablet strength used in addiction medicine, it has been FDA-approved since 1994 for alcohol use disorder and opioid use disorder — that is the dose behind the drinking research most people have come across. Compounded down to a small fraction of that strength, 0.5 to 4.5 mg, it becomes something else: low-dose naltrexone, or LDN, prescribed off-label for an entirely different set of symptoms.
The two are not interchangeable, and the evidence for one is not evidence for the other. Nuvari offers low-dose naltrexone only — LDN Flex-Dose, inside the Reclaim Protocol. This guide covers what LDN is, what clinicians actually use it for, what the published research does and does not support, and how a provider-guided titration month works.
Important safety note: Naltrexone blocks opioid receptors at any dose. It is contraindicated in anyone currently using opioid medication, in acute opioid withdrawal, or with acute hepatitis or liver failure.1 Tell every healthcare provider and any emergency personnel that you are taking it. Opioid use is screened before any prescription is written.
What Low-Dose Naltrexone Is — and How It Differs From the Standard Dose
Low-dose naltrexone is the same active molecule as the standard naltrexone tablet, compounded to a fraction of that strength at the dose a provider prescribes. It is non-sedating, non-habit-forming, and not a controlled substance. Because no manufacturer makes a commercial product at these strengths, LDN is compounded — and compounded medications are not FDA-approved.
The distinction between the two doses is the single most important thing to understand before reading anything else about naltrexone online, because most of what is written about the molecule describes the standard dose.
| Standard-dose naltrexone | Low-dose naltrexone (LDN) | |
|---|---|---|
| Strength | The full tablet strength used in addiction medicine | 0.5 to 4.5 mg, compounded |
| Regulatory status | FDA-approved for alcohol use disorder and opioid use disorder | Prescribed off-label; compounded and not FDA-approved |
| What the research addresses | Drinking outcomes and opioid-relapse prevention, under medical supervision | Pain, inflammation and immune-related symptoms — an area of ongoing research |
| Offered by Nuvari | No | Yes — LDN Flex-Dose |
Findings from studies of standard-dose naltrexone in alcohol-use populations under medical supervision do not describe LDN Flex-Dose, which is a much lower dose used for a different purpose — low-dose effects are an area of ongoing research, not an established use. A licensed provider determines whether naltrexone, and at what dose, is appropriate for you.
How LDN Is Thought to Work
At standard strength, naltrexone occupies opioid receptors continuously. At low doses, the proposed mechanism is different. A 2014 review in Clinical Rheumatology by Younger, Parkitny and McLain describes the pharmacology put forward for naltrexone at low doses: brief, transient modulation of opioid receptors, and activity at glial cells — the immune-signalling cells of the central nervous system.2 The authors describe early-stage human research and call for larger trials.
A 2018 review in Medical Sciences by Toljan and Vrooman covers how low-dose naltrexone is used in clinical practice and the mechanisms proposed for it, while noting that the evidence remains preliminary and based on small studies.3
That is the honest state of the science: a plausible and actively studied mechanism, a developing evidence base, and no established use. Anyone describing LDN with more certainty than that is ahead of the research.
What Clinicians Use LDN For
LDN tends to reach people through a particular door. It is often the conversation that happens after the labs come back normal — when someone has fatigue, pain that moves around, or symptoms that were never given a name, and the standard workup has come up empty.
The published reviews describe off-label clinical use clustering around a few areas:
- Chronic pain. A 2018 evaluation in Pharmacotherapy by Patten, Schultz and Berlau reviews the safety profile and the published clinical data for low-dose naltrexone in chronic pain and inflammation, and notes that LDN is generally well tolerated and that the evidence base is still developing.4
- Inflammation. The Younger review examines LDN specifically as a proposed anti-inflammatory agent, on the basis of the glial-signalling mechanism rather than on large outcome trials.2
- Immune-related and unexplained symptoms. The Toljan review catalogues the range of conditions in which LDN has been trialled or used off-label, with the same caveat attached throughout: small studies, preliminary findings.3
None of this establishes low-dose naltrexone as a treatment for any specific condition, and nothing here is a promise about how you would respond. Whether LDN is appropriate for you is a clinical determination made by a licensed provider who has reviewed your history. Individual responses vary.
How the Titration Month Works
Most prescriptions start where they end. LDN generally does not — the titration is the point. Nuvari's LDN Flex-Dose is built around a first month of adjustment rather than commitment.
- Week one starts low — 0.5 mg nightly. One capsule, taken at night. Starting at the bottom of the range gives your body room to adjust and gives your provider something to respond to.
- Provider-set steps, not a fixed template. Your provider decides when the dose moves and by how much, based on how you actually report feeling. There is no automatic escalation.
- Maintenance at up to 4.5 mg nightly. Titration completes when your provider settles you at the strength that fits, up to 4.5 mg. Because the dose is still moving, the first month bills monthly.
- Ongoing review. Dose adjustments after that continue to go through provider review. Tablets ship at room temperature; there are no injections and no special storage.
Common side effects can include vivid dreams, sleep changes, headache, and nausea — often during titration, which is part of why the ramp is slow.
Who LDN May Suit — and Who It Is Not For
It may be worth a conversation if you have persistent fatigue, pain or inflammatory symptoms that a workup has not explained, you would rather start at the lowest end of a range than at a fixed dose, and you want a prescriber who adjusts based on what you report rather than on a schedule.
It is not appropriate for anyone currently taking opioid medication or in acute opioid withdrawal, or for anyone with acute hepatitis or liver failure. It is also not a substitute for evaluating a symptom that has not been evaluated — LDN is prescribed after a clinical review, not instead of one.
And to be explicit: if what you are looking for is medication support for drinking, LDN is not that. That research is about the standard dose, which Nuvari does not offer, and it is a conversation to have with a clinician who treats alcohol use disorder. If you or someone you know needs immediate support with alcohol use, contact the SAMHSA National Helpline: 1-800-662-4357 — free, confidential, available 24 hours a day, 7 days a week.
What to Expect from Provider-Directed LDN
- Intake and evaluation. You answer questions about your health, history, current medications and goals online. Opioid use and liver history are screened. No in-person appointment is required.
- A provider decides. A US-licensed clinician reviews your intake, follows up on anything that needs clarification, and writes a prescription only if it is appropriate for you.
- The pharmacy dispenses. Your prescription is compounded and filled at a licensed US 503A pharmacy, then shipped — sealed, discreet, and room-temperature.
- You start at the bottom of the ladder. One capsule nightly at 0.5 mg, with your provider stepping the dose from there.
Provider-directed low-dose naltrexone is available through Nuvari's Reclaim Protocol.
For Nuvari's full drug safety information for this compound, visit nuvarihealth.com/importantsafety/naltrexone.
Frequently Asked Questions
Is LDN the same drug as the naltrexone used for alcohol?
It is the same molecule at a very different dose, used for a very different purpose. Standard-dose naltrexone is the strength that has been FDA-approved since 1994 for alcohol use disorder and opioid use disorder, and it is the dose behind the drinking research most people have read about. Low-dose naltrexone is a small fraction of that strength, from 0.5 to 4.5 mg, and it is prescribed off-label. Findings from studies of standard-dose naltrexone in alcohol-use populations do not describe LDN, which is a much lower dose used for a different purpose.
Does Nuvari offer standard-dose naltrexone?
No. The Reclaim Protocol is LDN Flex-Dose only — low-dose naltrexone compounded from 0.5 to 4.5 mg and prescribed off-label after clinical review. Nuvari does not prescribe or dispense standard-dose naltrexone, and nothing on this page should be read as an offer to. If you are looking for medication support for drinking, that is a conversation for a clinician who treats alcohol use disorder.
Why does LDN start at 0.5 mg?
The first month is built for adjustment rather than commitment. Starting at the low end of the range gives your body time to settle before the dose is raised, and it gives your provider something to respond to. Your provider sets each step and decides when, or whether, to move up — there is no fixed template, and maintenance begins when your provider says it should, up to 4.5 mg nightly.
Is low-dose naltrexone habit-forming?
Naltrexone is not a controlled substance and is not an opioid — it is an opioid-receptor modulator, and at low doses it is non-sedating and non-habit-forming. That said, it is contraindicated in anyone currently taking opioid medication or in acute opioid withdrawal, which is why opioid use is screened before any prescription is written.
How strong is the evidence for LDN?
Honest answer: it is developing, not settled. Peer-reviewed reviews describe how low-dose naltrexone is used in clinical practice and what mechanisms have been proposed for it, while noting that the published evidence remains preliminary and based on small studies, and calling for larger trials. Reviewers also describe LDN as generally well tolerated. Low-dose naltrexone is prescribed off-label; as a compounded medication it is not FDA-approved, and individual responses vary.
The Bottom Line
Low-dose naltrexone is a small dose of a well-characterised molecule, prescribed off-label, with a developing evidence base and a mechanism that researchers are still mapping. It is not the same thing as the standard dose used in addiction medicine, and the research behind that dose says nothing about this one.
What Nuvari offers is the low-dose version, with the titration month built in and a provider setting every step. What it does not offer — and does not plan to — is standard-dose naltrexone. If the symptom picture in this guide sounds like yours, the next step is a clinical conversation, not a purchase decision.
Sources
- U.S. Food and Drug Administration. ReVia® (naltrexone hydrochloride) tablets — Prescribing Information. DailyMed. Official label for standard-dose naltrexone hydrochloride; low-dose naltrexone is compounded and prescribed off-label, and this label covers the reference product. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=a46b4b3f-9d4b-4b9b-9866-2d3c0a88c620
- Younger J, Parkitny L, McLain D. "The use of low-dose naltrexone (LDN) as a novel anti-inflammatory agent: a review." Clinical Rheumatology. 2014;33(4):451–459. https://doi.org/10.1007/s10067-014-2517-2
- Toljan K, Vrooman B. "Low-Dose Naltrexone (LDN) — Review of Therapeutic Utilization." Medical Sciences. 2018;6(4):82. https://doi.org/10.3390/medsci6040082
- Patten DK, Schultz BG, Berlau DJ. "The Safety and Efficacy of Low-Dose Naltrexone in the Management of Chronic Pain and Inflammation." Pharmacotherapy. 2018;38(3):382–389. https://doi.org/10.1002/phar.2086