Not costo? I'm so sorry. I developed costo when I was 18 and was told that it was inflammation similar to pleursy and that it would disappear in a month or two. I'm 36 and still have it. Mine is usually during season changes. I live in Michigan so April and Oct are bad months for me. It does feel like your having a heart attack. The first few years I thought I was going to die and would run to ER often. Now, I pop a few tylenol and forget about it (yes, I know tylenol is horrible for the liver but the pain is also show-stopping) I am hoping to do some cleansing to eliminate the pain and a host of other problems. What nobody knew back then and still will not admit now is that the costo was probably a pre-cursor to many more problems about to come. I feel like costo was the beginning to my auto-immune problems but a md won't tell you that because they don't know. I have life-threatening severe allergies to fish which I developed about the same time as the costo. I just developed a peanut allergy and also sulfites so my system is all screwed up. I'm not sure if there is a chance of reversing these food allergies but significantly ligtening them up would be good. I would suggest taking a natural approach right now to the costo as you may ward off many other illnesses that will follow. The costo is scary but not life-threatening. Try and relax as the hypertension WILL make it worse.