Success Story from Parenthood.com
"Regarding Costochondritis: I have that problem. Not that bad, but was taking Ibuprofen 3x daily for it for several years, getting progressively worse. A guy at the health food store said it might be food allergies. I quit eating everything I knew I was allergic to and anything I suspected I was. Then I went on a gentle liver cleansing diet (with lots of raw veggies) for 3 weeks and it went away. My anxiety and seasonal allergies also cleared up. I was starting to think I should get checked for asthma but that also went away. As long as I am vigilant with what I eat it stays away. If I start eating junk again it starts to return. It's a pain to have to monitor my eating so much but the reward is well worth it.
Another line of thought could be parasites. Allergies and inflammation can sometimes be brought on by parasites. I traveled abroad and picked up 5 different parasites and bacteria, which went undiagnosed for 14 years, so maybe that's what caused such bad allergies in me. Maybe the liver cleanse cleaned out the parasites and that's what did it.
I have no idea if that's always the root of the problem or just mine. I just know what helped me. Hope you can find something here that might be helpful to you as well."