STUDresearch · Non-peptide
Low-Dose Naltrexone (LDN)
Also known as
LDN · naltrexone low dose · low dose naltrexone · low-dose naltrexone · ultra-low-dose naltrexone (ULDN) · very low-dose naltrexone (VLDN) · naltrexone (low-dose / compounding) · 4.5 mg naltrexone · Bihari protocol naltrexone (historical LDN framing)
Community talk. May be wrong. Not medical advice. Not a protocol. Not for human or animal use.
Non-peptide
Some talk
Systemic
Oral
Immune & inflammation adjacents
Systemic oral immune / neuroimmune modulator—not a local injection target.
What people say
Low-dose naltrexone is off-label oral naltrexone used at milligram amounts far below the labeled 50 mg addiction-treatment dose. It remains the same opioid antagonist, with condition-specific and mixed evidence.
Doses people talk about
These are separate self-experiments rather than a recommended ladder. The product, condition, schedule and co-medications were not controlled.
How it may feel
Early sleep effects vary sharply: vivid dreams, insomnia, morning jitteriness, later adaptation, better sleep, no pain benefit and intolerance all appear. The inspected same-author histories show that dose and dosing time changed alongside the experience.
Same-author dose history1.5, 3 and 4.5 mg at bedtime; 0.5 mg bedtime restart; later 1 mg morning and 7.5 mg
Vivid dreams followed the bedtime history; 0.5 mg was restarted at bedtime, morning jitteriness followed a later 1 mg dose, 4.5 mg did not relieve pain and 7.5 mg felt too jittery.
Step-increase sleep account0.5 mg increases up to 4.5 mg
The user described repeated insomnia and vivid-dream phases followed by normalization, including normal sleep after about a year at 4.5 mg.
Preserved core discussion rangeAbout 1–5 mg orally per day
Legacy literature and community framing; 4.5 mg is common but is not a universal target.
Half-life & effect duration
- Half-life in the body
- Naltrexone · oral labelAbout 4 hours
- Active metabolite · 6-beta-naltrexolAbout 13 hours
- Felt duration people report
- Sleep adaptation reportsDisturbing dreams for about 10 days or insomnia for about 2 weeks after changes
- Later reportsBetter sleep around 6 weeks, eventual settling, or no pain benefit
- Morning-use accountDaytime jitteriness
Cycles people discuss
Pain and autoimmune discussions usually describe continuous daily use evaluated over weeks to months, not peptide-style cycling. Long runs and re-challenges are community practice, while opioid transitions require clinical planning.
Timing
Nighttime use is the traditional community pattern; morning use is also discussed when vivid dreams or insomnia are troublesome. Empty-stomach and medication-spacing customs also appear in these discussions; they do not establish a better LDN response.
Stacks
Pain medicines, physical therapy, sleep routines and condition-specific treatments appear alongside LDN in the preserved notes. Multiple simultaneous changes make any benefit difficult to assign to LDN alone.
Watch for
Opioid blockade / withdrawal: Can precipitate withdrawal or blunt planned analgesia—central safety caution; washout days needed after opioids before milligram LDN.
Tap a line to jump into the full notes. Research only — may be wrong.
Timing context & sources
Half-life in the body
Naltrexone labeling reports mean elimination half-lives of about 4 hours for parent naltrexone and 13 hours for 6-beta-naltrexol.
The label also reports peak plasma levels of both within about 1 hour and dose-proportional exposure over 50–200 mg.
This is standard-dose label PK, not a dedicated 0.1–7.5 mg LDN pharmacokinetic study. Parent and metabolite elimination do not measure downstream immune narratives or subjective benefit.
- DailyMed — naltrexone hydrochloride tablets (opens in a new tab)Clinical Pharmacology reports oral bioavailability 5–40%, peak parent and 6-beta-naltrexol within 1 hour, mean elimination half-lives of 4 and 13 hours, and dose-proportional exposure over 50–200 mg.U.S. labeling for standard-dose naltrexone, not a dedicated 0.1–7.5 mg LDN PK study. The exact PK-study participants are not stated in the reviewed label section, and plasma elimination does not measure downstream or felt duration.
Felt duration people report
No single LDN felt-duration or adaptation window is established by the inspected reports.
Accounts range from disturbing dreams for about 10 days, to repeated roughly two-week insomnia phases after dose changes, to better sleep around six weeks, eventual normalization, no pain response, and daytime jitteriness after a morning dose.
Anonymous uncontrolled self-reports with changing doses, schedules, diagnoses and co-medications. Plasma elimination cannot be substituted for sleep, mood, pain or downstream immune timing.
- Reddit r/LowDoseNaltrexone — Might stop LDN because of horrible chronic dreams (opens in a new tab)Same-author thread and updates describe 1.5 mg at bedtime, then 3 and 4.5 mg with severe vivid dreams; after a one-week pause the author restarted 0.5 mg at bedtime for two weeks, then used 1 mg and moved that 1 mg dose to morning, reporting jittery/angry feelings until evening before moving it to 6 p.m.; later 7.5 mg felt too jittery and 4.5 mg did not relieve pain.Anonymous retrospective self-report with changing doses and clocks, unclear diagnoses and co-medications, no product verification, and no blinded comparison.
- Reddit r/LowDoseNaltrexone — Reached 4 mg, sleep discussion (opens in a new tab)Visible first-person replies include improved sleep at 1.5 mg after about six weeks; disturbing dreams for about ten days at 0.5 mg before a morning schedule; and one same-author step-up history in which each 0.5 mg increase brought roughly two weeks of insomnia, then vivid dreams, then normalization, with normal sleep after about a year at 4.5 mg.Multiple anonymous, uncontrolled reports with different conditions, products, dose histories and clocks. They show disagreement and adaptation narratives, not incidence or causal duration.
What people say
- Chronic pain clinics / observational: Retrospective series (e.g. ~115 patients, many fibro-related; final doses ~0.8–9 mg, mode 4.5 mg) report ~65% subjective pain/symptom benefit with confounded co-analgesics; not RCT proof. trialforum
- MS / neuroimmune: Small RCTs/series (e.g. Cree et al. pain/MS symptom work at 4.5 mg) discuss pain, fatigue, QoL—not disease-modifying like approved MS DMTs. trialforum
- ME/CFS: Polo et al. retrospective clinic series (n≈218 intention; 3.0–4.5 mg/day pathways): ~73.9% reported some positive response (vigilance/alertness, physical/cognitive performance common); ~18% no response; mild early insomnia/nausea common—no large confirmatory RCT yet. trialforum
- Long COVID / post-viral: Growing observational interest; RCTs (e.g. Australian, Canadian fatigue-focused, other ME/Long COVID designs) titrating roughly 1–1.5 mg toward 4–4.5 or 6 mg discussed—results not settled as of research cut. trialforum
- Hashimoto’s / thyroid autoimmunity: Strong functional-medicine and patient-community lore (energy, pain, fewer flares, TPO talk); controlled evidence thin; clinic notes warn thyroid replacement may need downward adjustment if autoimmunity quietens (hyperthyroid symptoms risk). forumanecdote
- CRPS / centralized pain: Variable, mostly uncontrolled logs and off-label clinic use. forumanecdote
- Mood / brain fog: Calmer days, clearer head common in logs—confounded by sleep, pain drop, and other meds. forum
- Sleep (secondary): Some sleep better after adaptation despite early vivid dreams; others never tolerate night dosing. forum
- Fibromyalgia pain (small trials): Younger 2009 pilot and 2013 randomized crossover (4.5 mg/day) reported greater pain reduction vs placebo in small samples (e.g. ~29% vs ~18% pain reduction cited for 2013); responders often defined as ≥30% pain drop plus fatigue/sleep improvement. trial
- Fibro response-rate talk: Younger has stated roughly ~3/10 may get meaningful multi-domain improvement in research framing—higher than some approved fibro-drug response benchmarks in his commentary, still minority. trialforum
- Fibro caveat / larger trials: FINAL parallel RCT (naltrexone 6 mg once daily × 12 weeks in women) did not show superiority over placebo for primary pain intensity; later re-analyses/meta-work debate pooled effect sizes and heterogeneity—claims of reliable fibro analgesia overstate the full picture. trial
- Dose–response fibro note: One dose-finding style analysis reported ED50 ≈ 3.88 mg and ED95 ≈ 5.4 mg with only 11/25 classified as LDN responders—supports individual MED hunting, not one magic number. trial
- Crohn’s / IBD: Smith open-label and related work: clinical response and remission signals at 4.5 mg (classic figures often cited ~89% response / ~67% remission in early open-label; later controlled/registry work more modest, e.g. clinical improvement/remission splits varying by study). Evidence still limited vs approved IBD drugs. trial
- Cancer adjacency (historical Bihari / LDN Research Trust talk): Off-label immune/endorphin framing and weekday-on/weekend-off cycling lore—not an approved oncology standard; CBD/THC combo talk exists in LDN Trust materials without robust confirmatory RCTs. forumtrial
Doses people talk about
- Core LDN band: ~1–5 mg oral daily is the usual “low-dose” definition; classic fixed target in many fibro/pain papers and forums is 4.5 mg once daily. trialforum
- Broader published/clinic range: Effective chronic-pain talk spans roughly 0.1–4.5 mg/day in reviews; observational work has logged finals from ~0.8 up to ~9 mg; fibro fund/community writeups sometimes cite 1.5–9 mg as the practical search range. trialforum
- LDN Research Trust dose ladder language: Starting often 0.5–1.5 mg, building toward 4.5 mg or highest tolerated; some conditions use split daily dosing; MCAS/allergy/malabsorption talk sometimes pushes higher totals or BID, including anecdotes totaling ~8 mg+. forum
- Classic weekly titration (common “fast” chart): Week 1 1.5 mg → week 2 3.0 mg → week 3+ 4.5 mg ongoing (nightly), if tolerated. forumtrial
- Slower autoimmune / sensitive schedule (Trust-style): 0.5–1 mg daily × ~14 days, then +0.5–1 mg every ~2 weeks to 4.5 mg or best tolerated—favored for ME/CFS, Long COVID, and highly chemo-sensitive patients in clinician interviews. forum
- Hashimoto’s / thyroid community start: Often 1.5 mg night (or 0.5–1 mg if sensitive), titrate toward 1.5–4.5 mg; separate from morning thyroid hormone by ~1 hour if AM dosing. Watch for hyperthyroid symptoms if replacement stays fixed while symptoms improve. forum
- Cancer-oriented Trust schedule (discussed, not standard oncology): 1.5 mg × 7 days, +1.5 mg weekly to 4.5 mg; cycling 5 days on / 2 days off (weekdays on, weekends off) commonly mentioned. forum
- “Do I have to hit 4.5?”: Compounding/Trust messaging emphasizes individual MED—some get full relief at 3 mg and lose it if forced higher; others need above 4.5. Fixed 4.5-only culture is debated. forum
- Ultra-low (ULDN): Microgram range, often cited ~1–2 mcg up to ~2–100 mcg/day—primarily adjunct talk with ongoing opioids to blunt tolerance/hyperalgesia; not the same use-case or mechanism emphasis as standalone milligram LDN. trialforum
- Very low (VLDN): Roughly 100–500 mcg (or broader <1 mg) for people who cannot start at 0.5–1.5 mg—bridge band in compounding kits. forum
- Timing — night (default lore): Once daily ~30–60 min before bed empty-stomach is the traditional Bihari/clinic instruction (short block + overnight rebound story). forumtrial
- Timing — morning switch: If vivid dreams/insomnia last >5–7 days, community and Trust guidance commonly move dose to morning; success rates described as roughly similar for autoimmunity goals either time. Separate other AM meds (esp. thyroid) by ≥1 hour; water-only window sometimes advised. forum
- Split / BID dosing: Used when sides at once-daily peaks, for some mental-health protocols, ME/CFS 1.5 BID examples, or MCAS higher-total strategies—total daily mg still the planning unit. forumtrial
- Compounding forms for accuracy: Custom capsules (1.5 / 3 / 4.5 mg common), liquid (finest titration), scored 3 mg tablets cut for 1.5, sublingual drops/troches for swallow issues or GI side reduction—not usually peptide-style inject. forum
- 50 mg tablet splitting: Discussed as imprecise (dose accuracy + commercial tablet fillers/binders); compounding preferred for true low-mg. forumtrial
- Immediate-release only lore: Extended/slow-release naltrexone is argued to keep blockade too long and blunt the rebound immunomodulatory story—compounders and Trust materials stress short-acting IR LDN. forumtrial
- If sides bite at 4.5 mg: Step down to ~3.0 mg (Younger research practice) or lower; many stay long-term at 3 mg with retained benefit in anecdotes. trialforum
- ME/CFS clinic example (Polo practice): Morning 1.5 mg × 1 week → 3.0 mg as 1.5 mg BID → after ~6 weeks may raise to 4.5 mg; stop if no effect by ~6 months. trial
- Micro-titration / MED hunting (Marcus chronic-pain observational method): Start 0.1 mg/day, +0.1 mg every third day (hold 2 days to assess), up to 6.0 mg/day max trial; may use divided doses then consolidate total daily MED into fewer doses. Designed because fixed 1.5/3/4.5 steps can miss the true minimum effective dose. trial
- Long COVID trial-style titration talk: Examples include start 1–1.5 mg titrate to 4–4.5 or 6 mg max tolerated. trial
- Framing: Discussed research, clinic, and community ranges only—not advice, not prescriptions, not a substitute for clinician compounding guidance. forum
How it may feel
- First days differ: One user said 0.5 mg brought disturbing dreams for about 10 days; another said each 0.5 mg increase brought roughly two weeks of insomnia before vivid dreams and later normalization. forum
- Dose and clock can change the report: A user moving 1.5 → 3 → 4.5 mg at bedtime described severe vivid dreams; after a pause, the same author restarted at 0.5 mg at bedtime, then later moved a 1 mg dose to morning and reported jitteriness and anger easing by evening. forum
- Weeks 1–2: Subtle ache or “inflammation noise” drop for some; others still only sides. Benefits often understated until closer to target dose if titrating. forum
- Later checkpoints conflict: One user reported better sleep at 1.5 mg after about six weeks; another described eventual normalization after repeated 0.5 mg increases, while a different author reported no pain relief at 4.5 mg and excessive jitteriness at 7.5 mg. forum
- Weeks 6–12: Typical formal trial window length (fibro 12-week designs; Crohn’s multi-month blocks); community “give it 8–12 weeks at a stable dose” mantra. trialforum
- Months 2–3: Pain/energy/flare claims consolidate—or people stop for non-response. ME/CFS retrospective practice sometimes continued up to ~6 months before labeling failure. forumtrial
- Month 3+: Often open-ended daily use when benefit holds—not short peptide-style cycles (cancer 5-on/2-off is the main cycle exception in Trust/clinic talk). forum
- No change by ~4–8 weeks at a true maintenance dose: Recheck expectations, opioid/OTC opioid-adjacent use, sleep, filler/source, and whether MED was never found—don’t jump to 50 mg “to force it.” forum
Cycles people discuss
- Default for fibro/autoimmune/pain: Continuous once-daily (or stable split) dosing—not bodybuilding on/off peptide cycles. forum
- Long runs: Months–years continuous when benefit holds and sides stay mild—common real-world pattern. forum
- Cancer-adjacent cycle: 5 days on / 2 days off at goal dose (often 4.5 mg) is the main structured holiday protocol in LDN Trust / historical clinic talk—not universal for pain/autoimmune. forum
- Holidays / travel pauses: Occasional reassess breaks appear in forums; not a required protocol. forum
- Re-challenge after washout: Common if symptoms return; re-titrate rather than slam full prior dose if prior sides were strong. forum
- Opioid-context washout (safety, not a “cycle”): Before starting milligram LDN, short-acting opioids often discussed as needing ~7–10 days free (longer for methadone/buprenorphine)—precipitated withdrawal risk even at “low” mg. trialforum
- ME/CFS practice stop rule example: No clear benefit by ~6 months → discontinue in one large retrospective pathway. trial
- Trial evaluation windows: Multi-week to 12-week blocks are the informal “did it work?” length in fibro RCTs; Crohn’s studies often ~12 weeks induction framing. trial
Timing
- Blockade window at LDN doses: Discussed as several hours of meaningful occupancy then fall-off—basis of “short block → rebound” model (exact occupancy curves at 1.5–4.5 mg less mapped than 50 mg addiction doses). trialforum
- Why once-nightly can still “cover” next day: Forums/Trust claim endorphin/immune downstream effects lasting ~8–18+ hours after levels drop—not continuous 24 h receptor blockade. forum
- Empty stomach rationale: Better/consistent absorption lore and separation from other meds; evidence for mandatory empty stomach is more tradition than large PK trials at LDN doses. forum
- Opioid interaction timeline: LDN + full agonists = blockade, blunted analgesia, or precipitated withdrawal—central hard stop in nearly all safety writeups. ULDN microgram co-use is a different, specialized opioid-adjunct discussion. trialforum
- Thyroid timing: Morning LDN users often separate levothyroxine/armour-type meds by ≥1 hour. forum
- Parent half-life: Naltrexone labeling reports a mean elimination half-life of about 4 hours after oral use; the same PK section documents dose-proportional exposure at 50–200 mg, not a dedicated low-dose study. trial
- Active metabolite: The label reports a mean 6-β-naltrexol elimination half-life of about 13 hours; that metabolite clock is distinct from parent naltrexone and from subjective benefit. trial
- Peak: Plasma peaks of naltrexone and 6-β-naltrexol often within ~1 hour oral. trial
- Oral bioavailability: Substantial first-pass; oral bioavailability estimates often ~5–40% (up to ~60% in some reports)—why oral charts are experience-based, not pure IV math. trial
More on what it is
- Dose-band vocabulary (LDN Research Trust / compounding culture): ULDN = microgram range; VLDN ≈ <0.1–0.5 mg; LDN ≈ ≤~4.5–10 mg daily (or split); moderate ~10–25 mg; high/standard ≥~50 mg. forumtrial
- Why people search it: Fibromyalgia pain, autoimmune flares, Crohn’s/IBD, MS fatigue/QoL, ME/CFS and Long COVID energy/PEM-adjacent talk, Hashimoto’s forums, centralized chronic pain, and compounding-pharmacy “cheap immune modulator” threads. forumtrial
- Mechanism talk (simplified): Short-lived μ-opioid blockade (hours) → endogenous endorphin/enkephalin rebound after levels fall; parallel TLR4 / microglial anti-inflammatory narrative (Younger et al. reviews heavily cited in community). Sustained endogenous-opioid upregulation in humans is hypothesized more than proven. trialforum
- Why bedtime became default: Brief night blockade timed to natural endorphin rhythms, then daytime “rebound” benefit is the classic Bihari / clinic rationale—not because the drug lasts all day at high occupancy. forumtrial
- Research lens: Forum “cured my fibro” posts and fixed 4.5 mg charts overstate certainty; responders, non-responders, and strong placebo effects all show up in the literature and logs. trialforum
- What it is: Pure opioid-receptor antagonist; full addiction/alcohol doses are typically ~50–100 mg/day; “LDN” means off-label milligram-range naltrexone, most often ~1–5 mg (classic community/trial target 4.5 mg). trial
- Evidence shape: Small fibro RCTs (including Younger crossover work) with modest signals; larger parallel FINAL trial (6 mg, 12 weeks) did not beat placebo on primary pain; Crohn’s open-label and small controlled work; MS symptom series; ME/CFS largely retrospective/case; Long COVID RCTs underway. Mixed, condition-specific, not definitive. trial
- What it is not: Not addiction-dose naltrexone, not a steroid or biologic, not FDA-approved for fibro/autoimmune/ME/CFS, not interchangeable with ULDN microdosing alongside opioids, not a peptide. trial
Stacks
- Fibro multi-modal baseline: Sleep hygiene, graded activity/PT, SNRIs, gabapentinoids, or other pain meds—outcome credit highly confounded. forumtrial
- Autoimmune adjacency supplements: Vitamin D, omega-3s, selenium/zinc (thyroid context), glutathione talk—often co-listed in functional-medicine LDN protocols without factorial trials. forum
- Hashimoto’s stack reality: LDN + thyroid hormone replacement is common; dose of replacement may need rechecking—not a fixed “stack ratio.” forum
- Gut / IBD: Paired with diet protocols, mesalamine/immunomodulators/biologics in case reports—not a standardized LDN+drug ratio. trialforum
- Cancer lore combos: Cannabinoid (CBD or THC/CBD) co-mention in Trust materials as possibly enhancing anti-tumor talk—anecdotal/historical, not guideline care. forum
- Peptide curiosity: Occasional BPC-157, thymosin alpha-1, KPV, LL-37 co-mentions in research-peptide forums; synergy unproven and confounded. forumanecdote
- Metformin adjacency: Sometimes co-searched in metabolic/autoimmune biohacking lists—no established LDN:metformin ratio. forum
- ULD N vs LDN stacking confusion: Do not casually combine microgram ULDN-with-opioids logic with milligram LDN immune protocols—different goals and risk profiles. trialforum
- Avoid / hard interaction: Full-dose opioid agonists (and often tramadol/codeine-containing OTCs)—blockade/withdrawal. Coordinate any planned surgery/analgesia washout. trial
Storage notes
- No mix instructions here: STUDresearch does not list reconstitution, diluent volumes, or syringe unit charts. People reconstitute many different ways and vial labels differ — that content creates more confusion than clarity. forum
- Storage (general talk only): Unopened research products are usually kept cool, dry, and away from light per the seller label. Anything after first use is product-specific — follow the label, not a universal forum SOP. forum
Watch for
- Vivid dreams: Most consistent early effect—Younger research ~37% vivid dreams on LDN (also high on placebo); can start night 1; usually fades over days–weeks. trialforum
- Insomnia / sleep fragmentation: Common early; lower dose, wait 5–7 days, or switch to morning are standard community fixes. forumtrial
- Transient symptom flare: Some report brief pain or fatigue increase during initiation (listed in ME/CFS clinic counseling). trialforum
- Mood spikes: Minority early irritability, anxiety, or emotional lability during titration. anecdoteforum
- Surgery / acute pain planning: Hold/timing coordination required so emergency opioids can work—clinical logistics, not optional lore. forumtrial
- Thyroid over-replacement risk (Hashimoto’s talk): If autoimmunity quiets, fixed T4/T3 doses may become excessive—monitor clinically. forum
- Compounding variability: Dose accuracy, fillers (esp. calcium carbonate debate), cost, and IR vs accidental modified release vary; gray-market powders riskier. forum
- Evidence humility: Responder rates well under 100%; large placebo effects; condition-specific signals; ongoing Long COVID/ME trials may change the map. trialforum
- Headache: Mild; appears in trial adverse lists. trial
- GI: Nausea, diarrhea minority; nausea > placebo in some fibro meta-analyses. trial
- Opioid blockade / withdrawal: Can precipitate withdrawal or blunt planned analgesia—central safety caution; washout days needed after opioids before milligram LDN. trial
- Not risk-free long-term certainty: Small-trial tolerability is generally favorable (sometimes comparable or better than placebo in fibro/Crohn’s writeups) but ≠ proven net benefit for every claimed use; FINAL-style null primary endpoints matter. trial
- Pregnancy / special populations: Sparse dedicated LDN data; standard naltrexone cautions apply in clinical contexts—community should not invent safety. trial
Evidence mix
Mixed trial + community tags
Full: every bullet (trial + community). Use Scan for a faster bro-science read.