The mucous membranes are highly susceptible to damage due to the activation of the stress response. This damage over time can affect susceptible women in such a severe way that most anything can irritate the tissue. IC varies in severity, but can be extremely uncomfortable and quite debilitating. This process can even extend into pelvic pain syndrome that affects the vaginal mucosa, as well.
Treatment of IC must include avoidance of as many triggers as possible: food allergies, acidic foods, oxalates, possible low-level infection, etc. This form of treatment is not the whole answer, however. It is essential that someone with IC also treat the underlying cause of the IC, which is a chronically triggered stress response system and Adrenal Dysfunction. To this date, I have not seen a woman in my office with IC who did not also have Adrenal Dysfunction. Treat the Adrenal Dysfunction and the IC is much more manageable, symptomatically, and you will also be able to cure the IC once and for all.