discussed at one of my regular reads. HG only has a mild case, though, and it appears to be exacerbated by pollen. She’s really, they say, having hay fever and her body confuses that with peppers and paprika.
Here are some old posts on the topic:
Nightshades Food List
Discussion of solanine in nightshades and how it isn’t really an allergy. But it acts like one. “A rose by any other name would smell as sweet.” And an allergy by any other name hurts.
A collection of internet comments on nightshades that were relevant to me or my family.
Night Shade Allergies, my post with the most comments, I think.