What Causes Severe Stomach Cramps Along With Dizziness And Weakness?

Dear Dr. Rynne:I periodically have very severe stomach cramps where I develop chills and become dizzy, weak and feel like I will pass out. I don t have normal nausea but if I stick my finger down my throat, I can usually throw up. These cramps start as my stomach hurting and then it builds. I am totally disabled during the cramps. They have lasted as long as 20 hours and as short as 5 hours. I have had every test under the sun and have even had my galbladder removed. I now know I have gastritis but my GI doctor said that would not cause the intensity of cramps. After an episode, I often have a bad bought of diarrhea. My GI doctor could not figure it out. I had all kinds of scans, endoscopies, colonoscopies, etc. He finally threw up his hands as gave up. He diagnosed it as the catch all IBS. Do you have any ideas? Thanks. Lasca Low