Low Dose Naltrexone


Naltrexone is a pharmaceutical drug, which was initially developed to treat alcohol addiction and drug abuse. In lower doses, naltrexone can treat symptoms of a number of mental and physical ailments including Alzheimer’s disease [1], Parkinson’s disease [2], mood disorders and PTSD [3], and many types of cancer [4].

The low dose naltrexone refers to taking this drug in a far smaller microdose than initially recommended for health purposes.

Also Known As


Editors’ Thoughts on Low Dose Naltrexone

Even though these are completely separate drugs, low dose naltrexone reminds me a bit of memantine in that they both were developed for alternative purposes, but found a home in the cognitive enhancement / biohacking communities for different reasons.

I’ve never taken low dose naltrexone before, but the anecdotal reports seem quite good for people suffering from specific health related problems. I can’t say I’d recommend it 100% for anyone who is interested in improving their mental performance because there is no real evidence that LDN can improve memory formation or learning in healthy adults in the same way as in Alzheimer’s / degenerative disease patients.

Either way, I think it’s a great alternative with some (note: some) positive research for people who are running out of traditional or supplemental options.

Mansal Denton, Nootropedia Editor

Low Dose Naltrexone Benefits

There are many potential benefits of low dose naltrexone, but primary among them is support for neurodegenerative diseases like Alzheimer’s and Parkinson’s.

In one 1986 study in the Journal of Neurology, Neurosurgery, and Psychiatry, scientists discovered that LDN could slow the degeneration associated with Alzheimer’s disease [5]. They also concluded that Alzheimer’s patients cannot regain lost function (debated today 30 years later) so it is best to start low dose naltrexone treatment earlier rather than later.

In a separate study on Parkinson’s disease, patients saw the disease reduce progression and the symptoms subsided. Some of the symptoms not commonly considered  (such as depression) were also cured in these patients [6].

Other benefits of low dose naltrexone center around anxiety and depression. In one study, those who suffered from extreme versions (post traumatic stress disorder) found a slew of positive effects from LDN. The 2015 German publication Der Nervenarzt concluded that low-dose naltrexone could treat patients with PTSD, though they noted a decrease of dissociation, which usually contributed to resolution in other studies [7].

Aside from the brain benefits of low dose naltrexone, there are many more common uses. One of the most popular is as a cancer therapy. One animal study found low-dose naltrexone could be coupled with chemo and radiotherapy as a unique treatment for cancer [8].

In fact, one particular study showed that out of 450 cancer patients, 75% had a reduction in tumor size and 60% demonstrated disease stability with low-dose naltrexone [9].

The primary purpose of naltrexone was for people with heavy drinking or drug problems. Studies show LDN can even help with addictive drugs like opiates [10]. While we might recommend natural alternatives like ayahuasca for the same purpose, it seems a useful alternative nonetheless.

Finally, there are many patients of HIV or AIDS and multiple sclerosis who find that LDN can help. With AIDS, a study found that 85% of patients had no detectable level of the virus after using LDN over 7 years [11].

Original Use for Naltrexone

The original use for naltrexone was for heavy drug and alcohol consumption. This is the purpose for which the FDA approved using naltrexone, but the doses were 50 – 300 times the low-dose recommendations by some modern researchers.

A researcher named Dr. Bihari (among many others) performed numerous studies and tests on patients using a lower dose of naltrexone to treat people. In almost all of his research, the treatment worked well. While a full dose of naltrexone can still be used for some purposes, many researchers now find low-dose naltrexone to be more effective and less invasive.

Low Dose Naltrexone Side Effects

Due to the FDA approval of naltrexone there has been research published on the side effects. One of the main side effects of low dose naltrexone is trouble sleeping and / or vivid dreams. Some people also experience nausea, gas, bloating, and an upset stomach [12].

According to anecdotal and research reports, most of the side effects of LDN subside quickly over the course of a few days or weeks, but this might not be a good methodology to maintain. Do not “stick it out” if you are feeling certain strong side effects.

It may be useful to speak to your doctor or healthcare provider about taking low-dose naltrexone to avoid any side effects that may come up.

Low Dose Naltrexone Dosage

The low-dose naltrexone dosage will depend heavily on your needs and it is probably useful to speak with a healthcare professional before getting started.

Traditional doses of naltrexone are in the 50 – 300 mg per day range, which is far higher than a standard low-dose. The dose range will probably be 1.5 – 4.5 mg per day.

It may be best to start slow and work your way up to a larger dose. Take LDN at bedtime in pill form for best results.

How and Where to Buy Low Dose Naltrexone

Naltrexone is a prescription drug so it is not something that you will readily find at a local health supplement or grocery store. Online it is similarly difficult to find because it is illegal to sell prescription drugs as supplements. In some countries this is not the case and there are millions of people who still use modafinil and armodafinil, so it is not a stretch to find and buy naltrexone online. One option is a product from IRC.bio.

However, the simplest (and safest) way for you to find naltrexone is through your doctor and a prescription. Sometimes there are online pharmacies that can help you to get naltrexone cheaper than the prescription pills at a local pharmacy.

Selected Community Experiences

“Only taken one dose during the day yesterday. But after a full nights sleep today has been great. Been suffering major fatigue, anhedonia, depression, some anxiety. Totally listless during the holidays. Quite lifeless and foggy. Today though I noticed my energy was up and steady while still being quite relaxed. Today has been the first day where it didn’t feel like some sort internal struggle. Will be taking this in the weeks to come at 4.5mg taking it before sleep.” – RJTolle [13]

“Recently I have started Low dose naltrexone. I take 1mg at night as of right now and I do notice an effect on mood, pain, energy. It is subtle but good enough for me to decide to go on using this long term.” – maf249 [14]

References (Click to Expand)
  1. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1029087/pdf/jnnpsyc00103-0109b.pdf
  2. //www.sciencedirect.com/science/article/pii/S1933721310000681
  3. //www.ncbi.nlm.nih.gov/pubmed/25421416
  4. //www.ncbi.nlm.nih.gov/pubmed/24511042
  5. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1029087/pdf/jnnpsyc00103-0109b.pdf
  6. //www.sciencedirect.com/science/article/pii/S1933721310000681
  7. //www.ncbi.nlm.nih.gov/pubmed/25421416
  8. //www.ncbi.nlm.nih.gov/pubmed/24511042
  9. //www.ncbi.nlm.nih.gov/pubmed/21807817
  10. //www.ncbi.nlm.nih.gov/pmc/articles/PMC3578306/
  11. //www.lowdosenaltrexone.org/ldn_aids_1988.pdf
  12. //www.ncbi.nlm.nih.gov/pmc/articles/PMC3962576/
  13. //www.reddit.com/r/Nootropics/comments/7oe8ua/feeling_awesome_after_low_dose_naltrexone/
  14. //www.reddit.com/r/Nootropics/comments/7gy2dm/using_low_dose_naltrexone_curious_about_other/


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