Has your GP or a registered dietitian screened you for the common nutritional deficiencies that occur secondary to longterm PPI use?

There are Quite a few nutrients that nerves need to stay healthy. Being deficient in any of them is a problem for maintaining structure and functioning of your nerves.

As well it would be informative to know why you are on this medication long term because there is perhaps other treatment options you can try or perhaps the condition you are taking it for may be known to cause neuropathy and that could be addressed.

Just one example of many.

Chronic Pancreatitis is associated with neuropathy. Perhaps because it creates deficiency of fat soluble vitamins like vitamin E that the nerves need to stay healthy . Or because Pancreatitis causes high levels of oxidative stress and inflammation not only to the pancreas but the surrounding tissues and the nervous system too.

And high levels of oxidative stress and inflammation , in order to fight that situation the body churns through high levels of multiple nutrients, like choline to name just one that nerves depend on to stay healthy.

You are going to have to be a bit of a detective to get to the bottom of this and you will also need to find a higher caliber of neurologist. Someone who is actually interested in helping you figure this stuff out.