Hey Rosally.I too get nausea before and after D. I actually get naseated in varying degrees with just bm's many times and it always depends on how severe the IBS is acting up. Last Saturday was a VERY bad nausea day and was terrible from the time of my first BM until around 5pm. I was sooo tired after that experience that I broke the plans I had and just went to sleep at 9.I do think the fatigue is related, at least in my case it is. I think when a person has to be afraid of "D" all the time it brings on extra anxiety which is energy depleting not to mention that I am nervous to begin with. There is also the stress that the body goes through physiologically FROM having D as well as possible dehydration. These days I try to drink fluids ALL day and that has helped some; however, a bad bout of D is likely to cause me to crash for the day.One last thing is I recommend getting checked for anemia because that can cause fatigue as well. I am iron and b-12 anemic and getting that somewhat under control has helped. Now, I go to bed at 9:30 instead of 7pm haha! Seriously though.take care