Bloody diarrhea can be a symptom of a very serious or a rather mild problem as there are many causes of bloody diarrhea.  However, letting this condition drag on untreated can have serious ramifications so seeking professional help is vitally important.  Gastric issues, life threatening emergencies, infections, medications and radiation treatments are among the most likely reasons for finding blood in one’s stool or having bloody diarrhea.  A series of tests performed under the supervision of a qualified physician will be needed on order to properly diagnose the underlying cause of this symptom.

Gastric Conditions that Cause Bloody Diarrhea

Bloody diarrhea is often caused by some type of gastric issue.  Problems in various points along the digestive tract can result in diarrhea with blood in it. More mild conditions such as hemorrhoids or an anal fissure are one of the most common reasons a person will see bloody diarrhea.  Diverticulosis, esophageal varices, polyps or tumors, colon or anal cancers and inflammatory diseases of the intestines are all common gastric problems that can cause bleeding and result in a patient seeing bloody stools.  While some of these conditions can be quite serious if medical attention is sought out early enough good results can be achieved.  Emergency issues such as a bleeding peptic ulcer, a bowel obstruction or a ruptured blood vessel need absolute immediate attention.  These gastric issues are serious and could have deadly consequences if left untreated.

Life Threatening Emergency Conditions

Aside from the gastric issues that can cause serious damage or loss of life when they become emergent, there are several other emergency situations that can cause gastric bleeding and that need to be addressed.  Abdominal trauma is often initially overlooked.  Last night someone was punched in the stomach and this morning he has bloody diarrhea, or perhaps he had his seat belt out of position and stopped on a dime, there was momentary pain in both cases.  These patients need to be seen immediately in an emergency room situation, just as the patient with a ruptured blood vessel or varices, a bleeding peptic ulcer, or other sudden and large bleeds also does.


One of the most common gastric infections is gastroenteritis.  In cases of serious infection or in cases that last over a long period of time a patient may end up with bloody diarrhea.  Most of the time gastroenteritis is caused by a virus; a particularly common stomach virus is called Norovirus which is extremely contagious and can be quite severe.  Another infectious cause of bloody diarrhea is food poisoning which is often caused by a bacterium, Salmonella.  This, too, is contagious. Infections with organisms like E. coli can also cause serious diarrhea and bleeding. Many of these infections are not actually food poisoning but are in fact caused by organisms that are carried from person to person through poor hygiene of food service or agricultural workers. Rarer infection by parasites, such as amoebic dysentery, can also cause bloody diarrhea. Generally, when the infection is treated or subsides if there is no permanent damage the gastric lining will heal and the bloody diarrhea will end.  It is important to never ignore this symptom and to see a doctor as soon as possible.  Medical intervention can mean the difference between a minor problem and an issue where permanent damage results.

Medication Side Effects

In some cases a simple medication such as an antibiotic can cause such serious gastric upset that a patient, especially someone on long term antibiotic therapy, will experience severe and even bloody diarrhea.  Chemotherapeutic agents, medications that treat depression and even prolonged use of steroids can cause bloody diarrhea.  Multiple medications can also cause patients to have severe and sometimes bloody diarrhea if they are withdrawn too rapidly rather than being tapered off over a period of time.  Bloody diarrhea caused by a medication can often be treated by simply switching to a more tolerable treatment.  These types of side effects are often quite individual, one patient might never have this symptom, but another might have a serious problem with the same medication.

Radiation Treatment

Patients who are having radiation treatment for cancer or other diseases will in all likelihood experience bloody diarrhea.  The lining of the gastric tract is very sensitive to radiation.  As treatments continue, patients will often experience diarrhea and possibly some gastric bleeding resulting in blood in the diarrhea.  Patients undergoing radiation therapy need to take care so that they do not become dehydrated during this time period.  Often a practitioner will prescribe something to slow or stop the diarrhea. 

Left untreated bloody diarrhea can cause serious problems, even if the initial underlying condition is not all of that serious.  Blood loss over a long period of time can cause major issues for the patient.  One of the common problems that are seen with patients who leave gastric bleeding unattended is anemia or a low red blood cell count. The most common complication faced by those who have this type of issue and leave it untreated is dehydration which can result in light headedness, loss of consciousness and other complications.  Kidney failure is another complication that may occur in severe cases.  Kidney failure is extremely serious and living with this condition can be life altering.  Patients with the most serious cases of bloody diarrhea may experience a large amount of blood volume loss which is life threatening.  Patients with sudden bleeds or with prolonged bleeds can slip in and out of consciousness and may even go into shock. It is absolutely essential that patients with bloody diarrhea get help from a medical professional; even though this condition may have a more minor underlying cause, blood loss can get quite serious.  Ignoring a problem of this magnitude will not make it disappear. Because the complications outlined here are quite serious and significant patients should not be uncomfortable or embarrassed to discuss their bloody bowel movements with a medical professional as soon as possible. No matter what the causes of bloody diarrhea are, seeing a medical professional will offer a solution and some peace of mind.