Quercetin’s ability to block mast cell activity is perhaps its most useful role in IC. An IC bladder has more mast cells than a healthy bladder. Mast cells are part of the immune system and found throughout the body. When activated, they release histamine and other inflammatory chemicals, such as heparin, prostaglandins, neutral proteases, acid hydrolases, chemokines and cytokines. Mast cells can be activated by an allergen, infectious agent, toxin, physical injury or even stress. By blocking mast cell activity, the inflammatory chemicals are not released and this spares the bladder from further irritation and destruction.
A couple of years ago I was suffering from what my allergist called chronic idiopathic urticaria and angioedema. His solution was a prescription of antihistamines, which kept them at bay initially. Eventually, though, I’d get breakthrough hives and swelling. When I suggested checking for gut dysbiosis since we were dealing with an immune reaction and I knew that 70% of your immune system is in the gut, he just dismissed the idea, saying there was no cure for my problem, that it would eventually go away and just double down on the antihistamines to keep the problem under control. Not being satisfied with that answer (actually, I called him a shill for the pharmaceutical industry), I went and found a functional medicine doctor who, after a bunch of tests, determined that, indeed, I was suffering from gut dysbiosis. She put me on an elimination diet to limit my intake of foods that would contribute to the dysbiosis, and gave me some suppliments to rid me of the overgrowth of certain bugs and finally had me take probiotics to repopulate my gut with the right bacteria. Once we completed the treatment regimen, the hives and facial swelling stopped and I haven’t had another case since.
In May 2002, Mast began feeling ill suddenly.  He had lost weight and was forced to miss races to take medical tests to find out what was wrong. It turned out that he had suffered carbon monoxide poisoning and Mast was forced to retire.  He officially retired on January 22, 2003 at age 45.  After his retirement, he spoke with NASCAR president Mike Helton about having teams redesign their air intake systems to get less exhaust fumes into drivers' helmets.  When NASCAR completely redesigned its race vehicle with the Car of Tomorrow , it changed the exhaust exit location to be away from the driver and it cited carbon monoxide poisoning cases like Mast's as a reason for the change.