Various types of alcohol have OTHER chemicals in them which may impact reactions on nerves.

Wine has sulfites in it, which some people cannot stand. Also polyphenols which are migraine triggers, and affect blood flow by dilation (causing burning sensations), and the congeners of metabolism by the yeasts=aldehydes which are the prime irritant IMO of nerve endings. B1 (benfotiamine) aids in the metabolism of aldehydes. A common drug Antabuse blocks aldehyde metabolism and causes nerve damage. Flagyl (metronidazole) as well interferes with aldehyde metabolism and causes PN.

Beer has active yeast also. And the aldehydes. People with gluten intolerance would react to beer.

Dark distilled spirits have all sorts of chemicals in them. The most benign spirit would be the poly-filtered vodkas, like Skyy or Smirnoff, or the really high end ones that advertise filtering.
Those would be the least of the irritants. But the ethyl alcohol itself will affect nerves in all the alcoholic drinks.

I just learned that gluten is not only a problem for those intolerant and/or Celiac, but it is a trigger for FODMAPS dietary
symptoms.

http://en.wikipedia.org/wiki/FODMAP
A low FODMAP diet is gluten free also. While FODMAP issues are mostly GI, they can set up an inflammatory response which may become irritating to the lining of the bowel, thereby letting in peptides into the body's blood stream to trigger autoimmune responses. The mainstream medical community is now accepting FODMAP as a source of some disease in humans. New research is just starting that examines the GI flora as damaged and thereby causing disease as well.

Eating a high carb diet is thought to lead to impaired glucose metabolism, and that leads to pre- or frank diabetes, with is a major cause of PN.

I know for me, eating spicy foods, nightshade veggies, and MSG will lead to a flare of burning for a day or two or more depending on what I ate. Not all PNers have this sensitivity, but many idiopathic ones may have this hidden, since some foods may delay symptoms by a day or two and not be easy to target.

This is why it is important for people coming here to look at how they live... when trying to find answers to PN problems. Something is in their environment that may be a trigger for it all. Add to that a genetic weakness that overtime is eroding health and bingo the nerves start screaming. And people will have various combinations of these two factors and no one is exactly alike. Even identical twins do not show 100% concordance for illness. Which suggests a huge environmental factor in addition to genetics.