Digestion Problems

[Lii1234]

For years I've had digestion issues, mainly constipation, but also diarrhea. The diarrhea is accompanied by painful lower abdominal cramps and in the past I've also had Vasovagal responses during these episodes (sweating, dizziness, nausea). Recently I've noticed white spots in my stool and then very large pieces of white (a bit of a yellow tint but mostly white) mucous? It looks like large pieces of fat in meat, sorry that's graphic, I know! I've had extreme fatigue for years which hasn't been explained by any other medical condition. Im 21, I exercise, eat healthy, im at a healthy weight, I eat a good amount of fiber, take vitamins, not sure what else to do. I've been to 2 different GI doctors and did not get any answers. They said I could do a Sigmoidoscopy but I've been nervous about it and haven't scheduled one. One of the doctors acted like it probably wouldn't be too beneficial. Are there any other tests I should push for? Looking for some answers!
Thank you!  

[Headcase2]

EGD and colonoscopy.  You need the EGD to check for Gluten Intolerance.Colonoscopy to check for microscopic colitis, etc..  let us know.  good luck.

[SickofDox]

Since this is a current GI post, I thought that I'd join and participate, since I'm also having loose stool and watery stools now for 8 months.
Since I traveled to different countries, and have also taken antifungals and antibiotics, I still have problems. All tests come back negative. I did read somewhere that if there are whitish pieces that it could be parts of parasites coming out in the diarrhea. I haven't had that description. Have you traveled? Have you eaten shellfish or raw oysters?
Just curious.