What Causes Abnormal Taste?

Hello, I am victim to an odd illness that occurs every now and then. It s not to frequent, the last time it happened was maybe a month ago. It really varies on occurrence. Anyway, It makes me belch, and the belch tastes highly revolting. I don t know what I would compare it to, I ve read online about people having this and saying it tastes like rotten eggs or something, all I know is it s an absolutely horrible taste. And along with that, typically there is diareah involved. I am experiencing it now. I m wondering what the cause of this is, what it is, and if there is treatment besides avoidance of certain foods as I am not sure what causes it. Thank you very much. This sickness has had a fairly major impact on my life and has greatly injured my self esteem. I would really like to know what I m up against. Also, a year ago, I was taking ibuprofen proactively everyday for an extended period of time. I used to think that I screwed up my stomach lining and stuff by doing that. Is that a possibility? Thanks very much