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Low-dose Naltrexone


1) Very potent, immune modulator properties and is supposed to help with pain. So start low and I mean LOW like 0.25mg if possible and increase SLOWLY (took me 2 years to go full dose 4.5mg). It causes me insomnia so I take mine very early (is supposed to be taken at night).
2) I take 9mg today (my pain was intolerable so Dr told me to) also Is supposed to raise NKs (which I have issues with too).
3) Is hard to get since it is special formulation and prescription so you need a special type of pharmacy that can formulate it. That I know of, it is not OTC.
4) I crash less while on it (not magic bullet) but every little help.
I Got very sleepy on it (literally could not function for weeks at the time) when I started, and got the best advice to try to stick with it. I am glad a did but it was not a walk in the park to get used to it.

Invisible Woman

Senior Member
There are a couple of different threads on LDN. Some if them go back a while and contain a lot of information.

If you use the search facility you should be able to dig out quite a lot of information with the added bonus that, if some of the previous posters are still "watching" the threads, they may be able to respond to any queries you post.


Senior Member
I take 4.5 mg every morning. Had to start with half that dosage. It takes away some of my muscle pain (am diagnosed with FM) but not all.
My local pharmacy produces capsules from Naltrexone.


Senior Member
Just read about this being used for fibromyalgia and fatigue (among many other things), wondered if anyone has been prescribed it and did it work?

https://www.ldnresearchtrust.org/sites/default/files/Dr Mark Shukhman.pdf
some people seem to benefit from it while for others it does nothing. Dosage is also affected by whether or not a person is taking opiates, and if so what dose of opiate. In my case I take opiates daily around the clock so only "Ultra Low Dose Naltrexone" (a very tiny dose) was appropriate for me to be prescribed. I was prescribed it by my ME/CFS specialist and unfortunately I experienced intolerable side effects within 12 hours of taking my very first dose. My doctor made me stop taking it immediately. I think my experience with the immediate pronounced side effects is a bit unusual but I like to share my story so that people know it is possible.


Senior Member
For me it reduces the muscle aches but has no other effects. I take 2.5 mg sublingually (pop the capsule open and dump it under my tongue). Sublingually reduces the required dosage about 1/3. Dosage is pretty critical: 2.0 mg doesn't do anything for me but 2.25 mg provides full reduction in aches. Above (I think it was 5 mg) lost the effect. It definitely needs personal trial-and-error to get the effective dosage for yourself. I only take it prior to a day I know that I really want to avoid the aches, because I don't like taking drugs unnecessarily.

charles shepherd

Senior Member
Basic information from the ME Association on Naltrexone


1 is an unproven and highly speculative form of drug treatment for ME/CFS and for all the other conditions like MS - where it is sometimes being used in the private medical sector

2 is unlikely to be prescribed by an NHS doctor for ME/CFS

3 could cause adverse effects, some of which are similar to, or the same as, ME/CFS symptoms - see below

We receive very mixed reports regarding both efficacy and safety. So in our current state of knowledge this is not a drug that we recommend or endorse

I would however point out that there has been one small clinical trial involving the use of naltrexone in fibromylagia, a condition that has some overlapping features with ME/CFS

Abstract, as published on MEA website:

From Arthritis and Rheumatism, 28 January 2013.

Low-dose naltrexone for the treatment of fibromyalgia: Findings of a small, randomized, double-blind, placebo-controlled, counterbalanced, crossover trial assessing daily pain levels†

Jarred Younger*, Noorulain Noor, Rebecca McCue, Sean Mackey
Department of Anesthesia, Stanford University School of Medicine, 780 Welch Road, Suite 207F, Palo Alto, CA 94304-1573



To determine whether low dosages (4.5 mg/day) of naltrexone reduce fibromyalgia severity as compared with the nonspecific effects of placebo. In this replication and extension study of a previous clinical trial, we tested the impact of low-dose naltrexone on daily
self-reported pain. Secondary outcomes included general satisfaction with life, positive mood, sleep quality, and fatigue.


Thirty-one women with fibromyalgia participated in the randomized, double-blind, placebo-controlled, counterbalanced, crossover study. During the active drug phase, participants received 4.5 mg of oral naltrexone daily. An intensive longitudinal design was used to measure daily levels of pain.


When contrasting the condition end points, we observed a significantly greater reduction of baseline pain in those taking low-dose naltrexone than in those taking placebo (28.8% reduction versus 18.0% reduction; P = 0.016). Low-dose naltrexone was also associated with improved general satisfaction with life (P = 0.045) and with improved mood (P =
0.039), but not improved fatigue or sleep.

Thirty-two percent of participants met the criteria for response (defined as a significant reduction in pain plus a significant reduction in either fatigue or sleep problems) during low-dose naltrexone therapy, as contrasted with an 11% response rate during placebo therapy (P = 0.05). Low-dose naltrexone was rated equally tolerable as placebo, and no serious side effects were reported.


The preliminary evidence continues to show that low-dose naltrexone has a specific and clinically beneficial impact on fibromyalgia pain. The medication is widely available, inexpensive, safe, and well-tolerated. Parallel-group randomized controlled trials are needed to fully determine the efficacy of the medication.


Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common
  1. Skin rash
  1. Abdominal or stomach pain (severe)
  2. blurred vision, aching, burning, or swollen eyes
  3. chest pain
  4. confusion
  5. discomfort while urinating or frequent urination
  6. fever
  7. hallucinations or seeing, hearing, or feeling things that are not there
  8. itching
  9. mental depression or other mood or mental changes
  10. ringing or buzzing in the ears
  11. shortness of breath
  12. swelling of the face, feet, or lower legs
  13. weight gain
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  1. Abdominal or stomach cramping or pain (mild or moderate)
  2. anxiety, nervousness, restlessness or trouble sleeping
  3. headache
  4. joint or muscle pain
  5. nausea or vomiting
  6. unusual tiredness
Less common
  1. Chills
  2. constipation
  3. cough, hoarseness, runny or stuffy nose, sinus problems, sneezing, or sore throat
  4. diarrhea
  5. dizziness
  6. fast or pounding heartbeat
  7. increased thirst
  8. irritability
  9. loss of appetite
  10. sexual problems in males
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Dr Charles Shepherd

Hon Medical Adviser, MEA


Senior Member
Los Angeles
unproven and highly speculative for ME/CFS and all other conditions?

I think the ME Association's info on LDN is a bit outdated.

My G.I. actually was completely on board with me taking it and was already well-versed in the research of LDN on Cronh's patients.

Also, I think the recommended goal of 4.5 mg is way too high. Most people who say they benefit from it, find it helps the most at around 1-2mgs. I personally got no advantages from 4.5 mgs, and went down to 1.5, and it worked very well.


Senior Member
Northcoast NSW, Australia
ve been using it for a few years. Wouldn't go without it. I was a member of several Yahoo LDN forums, people talked of using it for all manner of things. Given that more and more findings point to inflammation as a cause of illness, I think it's a wonderful boon.

I buy naltrexone tablets (alldaychemist, India), and mix the doses. very cheap.


Senior Member
Regarding side effects. LDN is not the same as Naltrexone in how it achieves its therapeutic effect, so the side effect profile may be different as well. Since in most medications side effects correlate strongly with dosage, I would find it at least logically likely that LDN (as in 1/10th of the standard Naltrexone dosage), would produce less side effects than Naltrexone. So I think it's incorrect to assume the side effects of Naltrexone automatically carry over to LDN.


Senior Member
I should also mention that I found that my 2.5 mg sublingual dosage worked just as well taken every 36 hrs. I alternated morning/evening every second day, at least when I was taking it regularly. Now I just take it when I really want the following day to be ache-free for some particular activity.

Those of you taking it regularly might give the 36 hr rate a try (or whatever works for you). I'm in favour of minimizing drug use, even if it seems like a really safe drug.


Forum Support Assistant
Also, I think the recommended goal of 4.5 mg is way too high. Most people who say they benefit from it, find it helps the most at around 1-2mgs. I personally got no advantages from 4.5 mgs, and went down to 1.5, and it worked very well.

I agree about the dose. 4.5 mg caused anxiety for me. 2.5 mg has been the ideal dose for the two years that I've been taking it. I read more often on PR that people benefit from a lower dose than 4.5 mg.

LDN is one of the few things that has significantly improved my life.

I wonder if the common CFS/ME hypersensitivity to meds and supplements is one reason why some of us need a lower dose?


Senior Member
Just read about this being used for fibromyalgia and fatigue (among many other things), wondered if anyone has been prescribed it and did it work?

I now take 4.5mg twice a day, and find it very helpful.

I consulted with the GP in Glasgow connected with Dicksons Pharmacy, someone with good knowledge of LDN in a range of conditions. He actually said that 4.5mg seems to be the sweet spot for hundreds of thousands of patients, but that twice that amount was still a low dose, and the only way to find out if it was more helpful was to try it and see.

I'm really glad of it, it makes a big difference.

My NHS GP said he's willing to prescribe it when there is trial evidence (having referred to the ME Assoc purple book :thumbsup:).


Senior Member
My experience with LDN is that I'm sensitive to it and I should not take more than 1.5 mg, preferably when I wake up, otherwise I experience too much insomnia and depression (depression kicks after some time). The benefit at 0.5mg-1.5mg is a better mood, less depression. So a higher dose has the opposite effect then the ultra low dose. No other benefit beside that.

Some people are more sensitive and can't stand a 3 mg dose or higher. One needs to experiment a little with LDN.
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Senior Member
I recently started on 2.5 mg dose. It helps with pain but I am surprised how much it helps my brain fog. Hopefully the benefits will continue.
Thanks for all your replies guys. For some reason I didn't get the notifications of posts! Looks like I have some reading to do.