It can be confusing to differentiate between
Naltrexone, Low Dose
Naltrexone and Naloxone. I have been reading other posts in the archives and see this.
Naltrexone is FDA approved to treat opiate addiction. The dose is usually 50mg
Low Dose Naltrexone is used off label to treat MS, Crohn's Disease, CFS, Lupus, some cancers, and very, very experimentally, Depression. It is not FDA approved for any of these uses, but it is not illegal to use it this way.