 [ Symptoms ] fainting nausea dark loose bowel associated with irritable bowel syndrome i have symptom similar to irritable bowel syndrome usually it happen very sudden acute stomach pain urgency to go to bathroom dizzy fainting nausea even vomiting in addition i have dark and loose stools it has been this way for long time i have this kind of episode several times should i see doctor [ Disease ] according to my research it is mainly to prevent heartburn or stomach upset if you are not experiencing this i would not worry