That sounds like an allergic reaction. Anaphylaxis ranges in severity from minor discomfort to life threatening. The reaction depends on the sensitivity of the person, the triggering substance, and the amount of the substance they came in contact with
Friend was one of those enthusiastic "go on, they're so fresh, try it you'll like it!" guys.
So I said: "all right then. Nope, still tastes like figs do"
Q: "What do you mean?"
A: "you know, all peppery and rough. Figs."
Q: "uh, what?"
A: "Figs are peppery, itchy, right? Right?"
"Nnnoo. It might be just you."
I don't have a serious reaction. I still don't like figs though.
I know one person that is allergic to chocolate, as well as to "Christmas trees" (don't know whether it's all pines or only some pines). Other than that, all the food allergy cases I know of fall into the common categories - dairy, poultry, shellfish, nuts/legumes...
Now that I think about it, I have to wonder if the "soapy" cilantro phenomenon is a mild allergy. But that's also correlated to the "supertaster" phenomenon.
Sensory phenomena are fascinatingly complex.
A reaction to that is quite common