Fecal vomit, also known as brown vomit, is not an urban legend. While it is not the norm and the human body is designed to try to prevent such a thing from happening, it is still something that will happen to a select number of people from time to time. If you are vomiting feces, or even think you are vomiting feces, it would be wise to seek medical attention immediately.
Feces in vomit, or vomit composed of feces in part, will be strikingly different than that of normal vomit. It will be brown in color, and have a distinct odor and taste. In many people that do vomit feces, but not all, they will begin to notice anywhere from several to a few hours beforehand that they have an odd aftertaste in their mouth when burping. They will often feel mildly nauseous at first, just as would be the case with a normal upset stomach. That is then normally followed by severe abdominal pain and bloating. The person will often find they are passing gas more frequently, and the gas will have a foul stench. Attempts to move bowels will often be unsuccessful.
Vomiting is a reflex of the body that is used to expel toxins - as is diarrhea. This is how the body gets rid of bacterial or viral infections. When food leaves the stomach, it enters the small intestine where it is processed into chyme which is a primarily liquid-like substance. The chyme then works its way to large intestine where it then is passed through the rectum. In some cases however, an obstruction of the bowel can cause a spasm which reverses the course of the excrement, or the blockage can cause waste to pile up until there is no other means of passage but out through the mouth. When one vomits feces, the feces will often look just as diarrhea would rather than as a stool.
Blockages can be caused by a few key factors which include a tumor, a twist in the intestinal tract, or fecal waste that has become compacted due to prolonged constipation which causes feces to backup into the stomach. Regardless of what it is that is causing the problem, it requires medical attention as soon as possible. When you vomit feces, your body is telling you in no uncertain terms that something is very wrong and you need help immediately. If the genesis of the issue goes untreated, it is likely that fecal vomiting will occur again. Ultimately, death is a possible result of the symptom of fecal vomiting left untreated.