Naltrexone is an opioid receptor blocker. Narcotics like oxycodone found in Percocet and hydrocodone found in Vicodin are opioids. When they bind to an opioid receptor narcotics regulate pain. We have natural narcotics (opioids) in our bodies called endorphins which also regulate pain and perform other functions.
There is a theory, with minimal scientific support, suggesting endorphins also regulate the immune system balancing both under or over production of immune system cells. This should help improve auto-immune illnesses where the immune system turns against us when it is over active like in rheumatoid arthritis or possibly in Lyme disease. Because it also helps to turn on an under-active immune system some believe it could also help in Lyme disease. Yes it is possible having a Lyme (borrelia) infection can trigger an autoimmune illness which causes things like pain and fatigue. On the other hand borrelia can also suppress the immune system.
Why is it low? What does it do?
Low dose naltrexone (LDN) is “low” because it is used at much lower doses than we use for people that have narcotic addictions (or overdose) and alcoholism. It is manufactured only as a 50 mg pill. When it is used to regulate the immune system, it is dosed at 1.5 to 4.5 mg a day. Compounding pharmacies that make medicines in house are able to produce naltrexone in low doses by crushing the 50 mg pill and dividing it into to “low” dose 1.5 to 4.5 mg pills.
At low doses LDN attaches to opioid receptors on temporary basis of around 4 hours. Sensing the blockade, the body produces more endorphins to overcome this. In theory increased endorphins then regulate the immune system.
Does it work?
There is limited science showing it helps in fibromyalgia, multiple sclerosis, and Chron’s disease. There is no research showing what it does in Lyme disease.
So what do I know? What do I do?
I have found it helpful in my practice in true auto-immune illnesses like rheumatoid arthritis, Hashimoto’s thyroiditis, ulcerative colitis, Lupus, and others. I have also seen it help in multiple sclerosis.
However, when I have tried it in Lyme disease I have not seen any benefit. And so I do not recommend it for most. I might try it in a person for which nothing else seems to help, so more as a last resort. I also might use it at the end of treatment when a person still has ongoing pain or even fatigue to see if these remaining symptoms are really auto-immune symptoms triggered by the borrelia infection.
I do not think there is any harm in trying the medication. In theory it is supposed to help within a few days or weeks of trying it. So I suggest a minimum of a two month trial to see if it will work. I usually start it at 1.5 mg a day for two weeks, then at 3.0 mg for 2 weeks, and finally at 4.5 mg a day on an ongoing basis.
by Marty Ross MD