Low Dose Naltrexone

In this post I’m going to be discussing low dose naltrexone, which is a treatment I primarily use for fibromyalgia.  I’ve also tried it for some other widespread pain conditions with success, but I’m going to focus on fibromyalgia because that is the best studied.  Low dose naltrexone, also abbreviated as LDN, is a relatively new therapy and is not officially approved for the use of chronic pain. I wouldn’t be surprised if in the future it does get approval for this, though.

Naltrexone is a medication that has been around for a long time and was originally created as an opioid receptor blocker. Opioids are medications like oxycodone and morphine. In order for these medications to cause pain relief, they bind to specific receptors called opioid receptors.  Naltrexone is similar to Naloxone (Narcan), which you’ve probably read about because it is a rescue medication for people who are experiencing an opioid overdose.

You may be sitting here wondering why, if I am trying to use a medication for pain relief, I would be using a medication that BLOCKS opioid receptors.  That doesn’t make sense right? But, with low dose naltrexone, the dose that is used is much much lower than the doses that are used to fully block those receptors.  And when we use low doses like this, the drug starts to have different effects and actually gives pain relief instead of blocking it.

Two popular theories exist as to how low dose naltrexone works, and it may be some of both.  The first is that LDN acts as a glial cell modulator. To understand what this means, we have to take a step back and talk a little bit about the nervous system.  The nervous system has many cells that are involved in communication called neurons. But, there are also many other “helper cells” that are involved in helping the nervous system to function properly and stay self-regulated.  These are the glial cells. It is possible that LDN may help these cells to function in a more healthy manner, which in turn, can lead to less pain.

The second theory involves the idea that when LDN blocks the body’s opioid receptors, the body may compensate by making its own opioids.  Everyone makes some of their own opioids at baseline, and these are called endogenous opioids. Endogenous just means “coming from the self”.  You can imagine, that if the body senses that its opioid receptors are blocked, it might try to overcome this by creating a little extra of its own opioids to balance it out.  These self-made opioids could potentially provide patients with pain relief.

The important thing is that there are a few small, but well designed studies, which showed that LDN had benefit for patients with fibromyalgia in terms of reducing pain scores and also improving mood.  Some of the studies also showed that it may help with fatigue. The really nice thing about LDN is that the side effects are very rare and manageable- mainly vivid dreams if they do happen. A lot of the other medications available for fibromyalgia can have difficult side effects that lead to patients discontinuing the therapy.

LDN is only available through a specialized pharmacy called a compounding pharmacy, because the only commercially made version of naltrexone is way too high- 50mg.  So this means that unless patients have compounding pharmacy benefits, the cost of the pills is completely out of pocket. The price varies a lot depending on the materials the pharmacy uses, and can be as low as 30-35 dollars a month and as high as $90-100.  

If you’re wondering if LDN might be helpful for you, the best thing to do is find a pain management specialist who is used to prescribing it and can make an assessment for you.  Don’t forget to subscribe to my blog by clicking on this link so you never miss a new post! Subscription link