Low Dose Naltrexone:

"I took Naltraxone for 2 years and it was fantastic, I can't take it now as I am on pain meds. Thanks God
I Hope this helps. I got mine from Skips Pharmacy in Boca Roton Florida, my Doc in Mass uses SKIPS exclusively." MM

"Both ____ and ____ are patients at Nancy Klimas's NeuroImmune Institute now located in Davie and Kendal, FL.
Both believe LD Naltrexone has been helpful.
Nancy's and her teams's approach has been to tweak what is outside the normal range of what can be measured in ME/CFS patients, and bring those parameters back into normal range - mostly by supplements."
KF

It is provided via prescription from compounding pharmacies.  Nancy Klimas' group uses two pharmacies.  One is in Boca Raton Florida and one in Colorado.  From Florida, one is initially given a very dilute liquid and some syringes to draw up and put in mouth to swallow very small amounts at first.  Then, as you are comfortable and have no ill effects, the amount is very slowly increased.  Then, the next bottle dispensed may be more concentrated and, again, you titrate yourself up to a specific number of milliliters.  You are given a chart to follow.  When you are at 3 grams of naltrexone, you might be given capsules of 3 grams to swallow.  Then, you reach the 'usual' low dose of 4.5 grams and get those capsules.  Also, the pharmacy in Colorado, for less money, dispenses 4.5 gram very tiny tablets.  The tablets cost 49 dollars, I believe for 90.  The pharmacy in Florida, Skip's Pharmacy, is a bit more expensive.  I think at first, it was about 49 for the bottle of liquid.  Not sure.  And, how long it lasts depends on the concentration and how much you are up to using.  Long story short, when you settle into the low dose of 4.5, you can get the three months for 49.  Both mail them to you if you are not local.  I have heard recently, from Nancy's colleagues, that one can try going as high as 9 mg, double the previously prescribed dose.  But, again, one titrates up slowly and might find that there are ill effects for an individual at some point between 4.5 and 9.  I do not yet know what these effects are. 

I hope this info is useful.