Acetyl carnitine has worked for people with toxic neuropathies and there are some studies on diabetics too more recently.

Chemo and HIV drugs were the first studied...and acetyl carnitine is now included in "longevity" formulas.

So yes, it is worth a try. We've had a few people for whom it did not help over the years. So it is not a "guarantee" by any means.

You'd best work up to 2 grams a day. You can start at 500mg a day for a week, increase to 500mg twice a day for a week, and increase by 500mg a day weekly until you reach 2000mg. It is not absorbed well, so taking a high dose all a once may waste it. So divide up doses during the day, and a greater % may be therefore absorbed.

This will show if you see improvements at lower doses, you won't need to get to the higher ones. Acetyl form is better absorbed than regular carnitine. It typically can cause GI upset, but only in very high doses 10 gram and above.

There are other supplements for mitochondrial support.
CoQ-10
Biotin
lipoic acid.

I found carnitine very helpful for muscle pain (after exercise). Carnitine helps the mitochondria burn fatty acids instead of glucose, so the lactic acid build up can be less with exercise. But it doesn't help my PN very much, so I don't take it regularly.

My PN is a mix of metabolic (hypothyroid), insulin resistance and arthritis. I do get burning, which can be worse with some foods, and MSG. I find that anti-inflammatory support helps my PN more. People vary.

iherb.com has some affordable choices. I used NOW and also Doctor's Best brands.