Rectal bleeding

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at December 7, 2015
StartSymptomsRectal bleeding

Bleeding can be frightening, especially when you do not know exactly where it is coming from. Occasionally, you may notice some blood on the toilet tissue, or in the toilet after having a bowel movement. This rectal bleeding can seem scary, but may only indicate a minor issue. However, bleeding that is significant, or continues, may be cause for concern, and should be checked out.


Definition & Facts

Rectal bleeding is defined as any bleeding that comes out through the anus. Blood may be seen in the stool, or on its own, and it can vary from a bright red color to a darker red, or even almost black. The rectum is actually the last few inches of the large intestine, and blood that escapes from the anus most likely came from that area.

Although most rectal bleeding does originate in the rectum, there is a chance that blood can come from other parts of the gastrointestinal tract, such as the small intestine or stomach, as well.


Rectal bleeding is usually caused by one of four relatively minor problems. First, anal fissures are tears in the lining of the anus that can bleed. They are painful and sometimes require surgery to repair. They are usually caused by hard stools. Hemorrhoids are swollen and inflamed veins caused by straining to have a bowel movement, and sometimes by pregnancy.

They can cause itching or pain, and can also cause bleeding, but are usually easy to treat with medication or minor surgery. Constant constipation and hard stools, which often go together, can cause small tears in the rectum or anus, which may also produce blood. Additionally, there are many other illnesses and diseases which can cause rectal bleeding. They are less commonly seen and can sometimes require more in depth treatments. These ailments can include:

When to see a doctor

Rectal bleeding that is accompanied by dizziness, lightheadedness, confusion, fainting, nausea, blurred vision, or rapid, shallow breathing requires immediate, emergency attention. Call for emergency medical assistance such as 911 or a local ambulance to transport the patient for care. You should also seek prompt care from a doctor if the bleeding is moderate or severe, or if it will not stop.

Bleeding that continues for too long can lead to further complications, so getting checked out quickly is critical. Additionally, if bleeding is accompanied by severe abdominal pain or cramping, or anal pain, you should not waste time getting to a doctor or urgent medical facility. Bleeding that is not severe, but lasts more than a few days should also be checked out.

Make an appointment with your doctor if you have rectal bleeding that has no known source. When there is rectal bleeding in which there is an obvious cause, such as constipation, the doctor will instruct you on how to treat that, but no further testing will likely be done, especially if you are under the age of 40. If the cause is less obvious, or if you are over age 40, it may require some testing to figure out what is going on.

Treatment & Therapy

Treatment of rectal bleeding will likely depend upon the cause of the bleeding. While it is important to determine the cause of all bleeding, one first must stop excess blood loss. This may be difficult if one has not determined the source of the bleeding, however. Additionally, if blood loss is significant, one must quickly replace blood to the patient’s body via a blood transfusion.

This will help alleviate further problems that can be caused by blood loss. In most cases, although it may look like a lot, there is only a small amount of blood lost, so the blood replacement step is deemed unnecessary. However, one still needs to find the cause of the bleeding to be able to eliminate it completely. The cause of the bleeding is usually determined by a patient’s history, and by physical examination. Doctors, such as gastroenterologists and colorectal surgeons, may perform tests such as anoscopy, flexible sigmoidoscopy, colonoscopy, radionuclide scans, visceral angiograms, and blood tests.

Many of these tests are used to check the inside of the rectum or colon, to find where the blood is coming from. Once the source of the bleeding is known, specific diseases can be determined and treated so that the bleeding can be stopped. For example, some diseases such as ulcerative colitis can be treated by medication which controls the symptoms, and reduces or eliminates bleeding.

In addition, polyps found by a colonoscopy can be removed surgically and cauterized if needed, and cancers can often be treated. Hemorrhoids can be also be treated with medication, and the source of the hemorrhoid can often be eliminated with the proper diet. Anal fissures can sometimes heal on their own, or they can be repaired by surgery. Constipation and hard stools can easily be controlled by a diet that includes more fiber and plenty of water.

Prevention & Prophylaxis

Knowing the cause of rectal bleeding is a big step towards being able to prevent future episodes. For example, if a bleeding polyp is the cause of your rectal bleeding, having it removed will ensure that the bleeding will not occur again in the future, at least fromthat source. In general, however, the best strategy to avoiding the most common cause of rectal bleeding is to avoid constipation.

Eating a diet rich in fruits and vegetables, including at least 25 grams of fiber daily, and drinking plenty of water daily will help you to have regular bowel movements. Additionally, there are some foods you may wish to avoid completely. Foods or beverages containing caffeine or alcohol can dehydrate a body and cause constipation. Also, sometimes dairy products and other foods can cause problems in the colon which could lead to rectal bleeding.

Avoiding these items may help you avoid any bleeding issues. Similarly, you should avoid sitting on the toilet for too long or straining to have a bowel movement, both of which can cuase hemorrhoids. Remembering to follow healthy practices will go a long way to avoiding rectal bleeding.