Alright, so ever since I can remember, i've been getting stomach pains, sometime being so bad i'm doubled over in pain, gritting my teeth. I have diarrhea sometimes, but also constipation other times. I have an extremely hard time gaining weight, and my appetite has been getting lower and lower as time goes by. When I go into work, almost every time, someone tells me I look like crap. Im a 22 year old guy, but I weigh about 114 lbs. I sometimes feel nauseous after eating small things. I got a colonoscopy, followed by a gastroscopy, and both turned out clean. My gastroenterologist said it might be IBS. Is the quality of life for IBS sufferers supposed to be this terrible? My gastro gave me a prescription for Protylol, and said to take one when it gets bad. But my questions is, can I just take one during any stomach problem? What are the side effects? I'm working and going to school, so bad side effects are not good.I feel like i'm always at the doctor. Im so tired of this.