Has anyone tried treatment for diabetic neuropathy?

My dad (age 60) was recently diagnosed with diabetic neuropathy and I have been researching all about it this past week. I know there is no cure but I have run into multiple treatment centers that claim they can help alleviate the pain. My dad lost so much weight recently, I could barely recognize him and it scared me half to death, and he can't sleep through the night because of the pain. Has anyone tried Loma Linda's INF treatment or HFX spinal cord stimulation? The meds given by his doctor don't seem to help much so I am also going to try to give him some medicinal edibles to sleep through the night.

Thank you to anyone who can give me some insight.