My dad takes it in a pill form for alcohol addiction and he has no side effects at all.
Naltrex is primarily used for Alcoholism. It has proven to work Very Well. Not so much for opiates......there workin on it.........
Takes away cravings for booze, I believe it is one injection --not sure how long it lasts, but people swear by it........It's not promoted as well as it should be.
Side effects.........I don't know......heard nothing but good things.
Luv,
Nauty.......