Eric,The weight loss resulted because of a very severe flare-up of IBS-D. I had watery diarrhea 8-10 times a day, every day for about 2 months. I then got to the point where I just couldn't eat...everything would come right back out within 15 minutes of eating...undigested. For about 2 weeks, all I ate was oatmeal in the morning, and toast. I was trying to do the BRAT diet to get the diarrhea to stop. I tried the calcium (lnappe's suggestion), but I couldn't tolerate the increased gas it gave me. I finally was able to get the doctor to prescribe meds for me. I tried Elavil first, since I had been on it previously, and it worked pretty good for about 5 years. But, it did not help...actually made the pain, cramping, etc, worse. So, finally, I was put on Levsin SL. With the first dose, the cramping, pain, and diarrhea stopped. By this time, I had lost 15 pounds. My weight has been pretty steady since then. The doc didn't say much about the weight loss, cause i told him that I was afraid to eat, cause of all of the diarrhea. he just said this last time I was in the office (12/6), that I was dangerously thin. No suggestions on what to do, other than to drink milkshakes...well, can't do that...I am lactose intolerant.I recently was put on Synthroid, and I have lost another 2 pounds.All of my labs,tests, etc., have been normal, except for the TSH (thyroid stimulating hormone). It was elevated, hence the reason for the Synthroid.Now, what do I do?MJ