Rectal Bleeding (Bloody Stool): Causes, Characteristics & Treatment

What is Rectal Bleeding?

Rectal bleeding, or hematochezia, refers to bleeding through the anus (x). The blood is often accompanied by stool and it may even form blood clots. In most cases, the source of bleeding is the colon, anus or rectum and it also may be related to diarrhea (x).

The source of the bleeding determines the color of the blood. The blood is likely to be a bright red color if the source is near the anus. If the source is the colon, anus or rectum, the blood will also appear bright red. On the other hand, if the source of the bleeding is in the transverse colon and right colon, the blood is more likely to be dark red (x).

Characteristics of Rectal Bleeding


Some patients may experience bleeding that is black, sticky and foul-smelling. This type of bleeding is called melena. Melena occurs when the bleeding is in the colon and if bacteria digests it on the way down. Therefore, melena indicates that the source of the bleeding is the stomach, duodenum or the small intestines. However, the source may also be in the right colon (x).

In some cases, patients experiencing melena may also vomit. The vomit may be bright red or brown and it may look like coffee grounds (x). However, some food and antibiotic medications may give the stool a red or blackish appearance and patients may confuse this with melena (x).

Bright Red Blood

Rectal bleeding may cause bright red stool if the blood does not stay in the digestive tract long enough for bacteria to break it down. If the blood stays in the digestive tract longer, it looks less like blood when it leaves the body in stool (x). The source of this type of bleeding is usually the sigmoid colon and rectum (x).

Occult Blood

In some cases, the blood may move through the digestive tract too slowly to cause bright red blood or melena. In such cases, the bleeding may not be visible to the naked eye. This condition is called occult bleeding (x). Patients with occult bleeding may not notice any changes in the color of their stool.

Accompanying Symptoms

Rectal bleeding may come with other symptoms depending on the location of the bleeding. If there is massive, sudden bleeding, the patient may experience weakness, dizziness, shortness of breath and abdominal discomfort or cramping (x). The patient’s blood pressure may also drop and they may have pale-looking skin (x).

Causes of Rectal Bleeding


This condition is the most common cause of rectal bleeding. It causes the veins in the anal and rectal area to swell. The symptoms include bleeding and a painful burning sensation in the lower abdomen. Hemorrhoids are grouped into two categories: external hemorrhoids and internal hemorrhoids (x).

External hemorrhoids are usually small, painful, visible swellings (x). They usually cause anal itching and hard, tender lumps near the anus. On the other hand, internal hemorrhoids may be painless, but they often cause bleeding after a bowel movement or the hemorrhoid may fall through the anus. Internal swelling in the rectal or anal veins may also cause pain and difficulty passing stool (x, x).

Hemorrhoid treatment involves prescribed pain relief medication, stool softeners or bulking agents. In some cases, the swollen veins may form clots, which may cause pain and may require surgery to remove the thrombosis (x).

Anal Fissures

Hard stools may cause the rectal lining to tear, which can cause rectal bleeding. Bleeding from anal fissures is usually mild and bright red. The tear may expose nerves and blood vessels, causing moderate to severe pain. The symptoms of anal fissures typically decrease with stool softeners and bulking agents, as well as frequent warm water baths, fiber-rich foods and pain control medication (x).


This condition causes pouches called diverticula to develop and project from the bowel walls (x). The leading cause of diverticulosis is a lack of dietary fiber (x). When the diverticula become inflamed or infected, it causes diverticulitis. This condition mostly affects people older than 40 because age negatively impacts diverticulosis symptoms (x).

Dark red or maroon stool is a common symptom of diverticulosis (x). This condition is usually painless and asymptomatic, but when it does cause pain, the patient usually feels it in the lower left side of the abdomen. Other symptoms include constant bleeding, fever and stomach pain. This condition is usually treated by eating more fiber-rich foods (x). However, severe cases may require surgery.


An infection in the rectal or anal area may cause rectal bleeding. The primary source of such infections is bacterial dysentery, caused by salmonella and E.coli. Signs of infection include bloody diarrhea, fever and abdominal pain. Antibiotics treat gastrointestinal (GI) infections (x).


Another common cause of rectal bleeding is inflammatory bowel disease (IBD). Most commonly, it affects patients in their 20s or 30s (x, x). The most common types of IBD that cause rectal bleeding are Crohn’s disease (x) and ulcerative colitis (x). Inflammation may cause small to moderate amounts of bright red blood in the rectum. Oftentimes, it is mixed with stool or mucus. Fever and abdominal cramping and pain are also associated with IBD. Bowel rest and steroid therapy can help relieve it (x).

Crohn’s disease causes rectal bleeding less often than ulcerative colitis (x). However, with Crohn’s disease, the location of the inflammation determines the severity of the bleeding (x). This condition is likely to cause rectal bleeding if it affects the colon or the rectum, but it is less likely to cause bleeding if it affects the small intestines (x).


This condition causes inflammation in the veins and capillaries in the walls of the colon (x). The inflamed areas may become fragile and start to bleed. Angiodysplasia is more common in older adults (x).

Colon Polyps

This condition is characterized by bulging tissues from the lining of the colon (x). Large colon polyps may begin to bleed through the rectum. This condition may be hereditary and in some cases, the polyps may become cancerous (x, x).


Both benign and malignant tumors in the colon and rectum may cause rectal bleeding. This condition usually affects people older than 50. However, colon and rectal tumors can also develop in younger people (x). The tumors typically cause minimal and slow bleeding. But advanced rectum or colon tumors may cause weight loss, constipation and changes in stool. The patient may also feel pain in the anal area (x, x).


Sometimes, rectal bleeding can result from injury and if this is the case, it should be a serious concern. For example, a gunshot wound or a foreign object inserted into the rectum can cause trauma (x). This type of bleeding can cause extensive infection or massive blood loss (x). Rectal bleeding as a result of trauma requires immediate medical attention. 

Upper Gastrointestinal Bleeding

The stomach and duodenum are two of the most common sources of internal bleeding that cause bloody stool (x). For example, if a patient swallows a foreign object, it may cause stomach injuries. When there is a tear in the mucous membrane where the esophagus meets the stomach lining, it causes Mallory-Weiss syndrome, which may cause rectal bleeding (x). But the most common cause of these tears is forceful vomiting (x).

Meckel’s Diverticulum

This is a very rare condition characterized by a bulge in the small intestine. It develops in fetuses very early in pregnancy. The vitelline duct connects the fetus to the yolk sac and it is usually absorbed seven weeks into gestation. If it isn’t fully absorbed, the fetus develops a Meckel’s diverticulum that contains cells from the stomach and the pancreas. The stomach cells release acid, which can cause ulcers and bleeding.

The symptoms usually develop by the time the child is a year old and usually include bloody stool from the ulcers in the small intestine. Meckel’s diverticulum may also cause abdominal pain, diverticulitis and bowel obstructions that cause stomach cramps, diarrhea, constipation, vomiting and bloating. Anyone can have a Meckel’s diverticulum, but it is most common in older children. Adult patients can develop tumors, although it is rare (x, x).

Rectal Bleeding in Children

If a child experiences rectal bleeding, please take it seriously. Some children may require immediate hospitalization for evaluation. The main cause of rectal bleeding in children is intussusception, which causes one part of the bowel to slide into another part. It blocks the bowel and can cause intestinal swelling and bleeding. It may also cut off blood supply to the intestine and destroy the bowel. Intussusception usually occurs within the first year of a child’s life (x, x).

Rectal Bleeding during Pregnancy

One of the leading causes of rectal bleeding during pregnancy is hemorrhoids. They are more common during the second and third trimesters (x). Constipation and straining during bowel movements may aggravate hemorrhoids (x). Pregnant women who experience rectal bleeding should consult a doctor immediately.

Causes of Bloody Stool

When to Seek Medical Attention

Mild and occasional rectal bleeding is common and usually does not need medical treatment. However, it may also indicate a serious medical condition. To be safe, it is best to seek immediate medical attention if the bleeding is accompanied by (x):

  • Fever
  • Nausea or vomiting
  • Coughing or vomiting blood
  • Weight loss
  • Changes in bowel habits
  • Black or dark red stool
  • Abdominal pain or swelling

Treatment for Rectal Bleeding

The cause and source of the bleeding determine the treatment. However, if the patient does not know the cause of the bleeding, the first thing the doctor will do is ask about the patient’s medical history. The doctor may also recommend additional tests depending on the severity and the accompanying symptoms. Significant blood loss may require hospitalization. Patients may also be hospitalized if the bleeding has not stopped or if their vital signs do not return to normal (x).

Home Remedies for Rectal Bleeding and Digestion

Home remedies may minimize rectal bleeding, such as rectal ointments (x). If the symptoms persist, see a doctor for immediate evaluation and treatment. Home care remedies that may prevent or manage the sources of rectal bleeding include (x, x):

  • Drinking lots of water
  • Avoiding straining when passing stool
  • Cleansing the anus gently
  • A high-fiber diet
  • Avoiding alcohol
  • Maintaining a healthy weight
  • Avoiding spicy, fatty, heavily processed food

Supplements for Healthy Digestion

Psyllium Husk

Derived from plantago ovata seeds, psyllium husk grows all over the world and acts as a natural laxative, absorbing water and moving waste through the digestive system. According to studies, it may help relieve constipation and ease diarrhea. As a dietary supplement, the recommended dosage for psyllium husk is 5 grams (about 1 tbs.) one to three times per day with water unless a physician recommends a different dosage. 

Flaxseed Oil

From the plant Linum usitatissimum, flaxseed is a natural plant-based protein. It hosts manganese and thiamine and also has fiber in its outer seeds. When a patient consumes flaxseeds with water, they expand in the stomach and break down in the digestive system and bind with cholesterol in the intestines. Take one to three flaxseed oil softgels per day with food, unless a doctor advises otherwise.

The Bottom Line

Rectal bleeding refers to bowel movements that contain blood or blood clots coming out of the anus. It may be triggered by many factors including trauma, infection, hemorrhoids and anal fissures. The color of the blood may vary depending on the location and severity of the bleeding. Bright red blood usually originates from the rectum or anus. But dark and tarry blood may be a sign of prolonged bleeding in the colon.

The location and severity of the bleeding also determine the treatment. In some cases, the patient may require surgery to treat the underlying condition. See a doctor immediately if the bleeding is a result of trauma or if the condition causes fever, nausea, vomiting, weight loss, excessive abdominal pain or if the patient coughs up blood. Also, supplements may be able to promote healthy digestion and prevent bowel changes as well as some of the GI problems that cause rectal bleeding. However, supplements are not an adequate medical treatment. Always seek medical advice and consult a doctor before starting a supplement regimen.

Author: BulkSupplements Staff