Capsaicin, the ingredient responsible for the pungent taste of hot chili peppers, is widely used in the study and management of pain. Recently, its neuroprotective effect has been described in multiple studies.
The opposite pathway may also be true [58]. The secondary subtype is caused by surgical removal of mucus secreting cells, stress, or granulomatous diseases, and is characterized by fetor, crusting, and nose congestion [58].