Rectal bleeding usually refers to bleeding from the anus, rectum, or colon, all of which are the final portions of the digestive tract.

A few occasional drops or streaks of blood in the toilet when wiping or in the stool are usually not a worry. In fact, certain foods, such as blackberries, dyes, tomatoes, and others, can give stool the appearance of blood. In these cases, the appearance should go away within 12 days.

However, in some cases, bright red blood in the stool may indicate bleeding in the lower colon or rectum. Darker red blood is a sign of bleeding in the small bowel or upper colon. Very dark or black-red blood often means there is bleeding in the stomach or other organs of the digestive system.

This article reviews 11 causes of rectal bleeding, along with additional symptoms of each, and when to see a doctor.

There is a wide range of reasons for blood in the stool. Many health conditions and factors can cause or add to rectal bleeding.

Some of the most common causes include:

1. Hemorrhoids

Hemorrhoids are inflamed anal blood vessels. They are very common, affecting about 1 in 20 people and about 50% of Americans over the age of 50. They can develop on the outside or inside of the anus, appearing as small bumps that occasionally bleed during bowel movements or when wiping.

Hemorrhoids, which people may refer to as piles, can impact anyone of any age, but some people have a higher risk of developing them. A few risk factors include:

  • pregnancy
  • chronic constipation
  • chronic diarrhea
  • straining during bowel movements
  • often lifting heavy objects
  • sitting on the toilet for too long
  • obesity
  • low fiber or unbalanced diet
  • being over the age of 50

Hemorrhoids usually respond well to over-the-counter (OTC) creams and suppositories that contain hydrocortisone. Taking warm baths frequently, eating a high-fiber diet, and using stool softeners can also help reduce the discomfort of hemorrhoids.

If initial treatments fail, a doctor may perform minor surgery to remove the hemorrhoids.

2. Fistulas

A fistula occurs when an abnormal opening or pocket develops between two neighboring organs. Fistulas that appear between the anus and rectum, or anus and skin, can cause a discharge of white fluid and blood.

Doctors sometimes treat fistulas with antibiotics, but they may require surgery if they progress.

3. Fissures

Anal fissures occur when tissues lining the anus, colon, or rectum tear, resulting in pain and rectal bleeding. In some cases, passing a hard stool can cause a tear. When they occur, they often cause bright red blood when passing a bowel movement.

Warm baths, a high-fiber diet, and stool softeners can all help reduce symptoms of fissures. In severe cases, fissures may require prescription creams or surgery.

4. Diverticulitis

Diverticulitis occurs when small pockets called diverticula develop on the walls of the colon around a weakness in the organ’s muscular layers.

These pockets are very common. Sometimes diverticula can start bleeding, but this usually stops on its own.

The pockets do not usually cause symptoms or require treatment unless they become infected.

Infected and inflamed diverticula often cause pain and can lead to rectal bleeding — usually a moderate flow of blood that lasts for a few seconds.

However, diverticular bleeding can at times result in a significant amount of blood loss. For this reason, a person should immediately seek medical attention. A person can recognize they may be experiencing diverticular bleeding if painless bleeding is coming from the rectum.

Doctors may treat diverticulitis with antibiotics and, in severe cases, surgery.

5. Proctitis or colitis

Proctitis occurs when the tissues of the rectum become inflamed, often resulting in pain and bleeding.

Colitis occurs when the tissues lining the colon become inflamed. A type of colitis, called ulcerative colitis, can also cause ulcers, or open, progressive sores, that often bleed.

Treatments for proctitis and colitis vary, depending on the causes. They range from antibiotics to surgery.

Common causes of proctitis and colitis include:

  • infection
  • some conditions that cause digestive problems, such as Crohn’s disease
  • some medications, such as blood thinners
  • radiation or chemotherapy
  • anal intercourse
  • reduced blood flow to the colon or rectum
  • a blockage in the colon or rectum

6. Gastroenteritis

Bacterial infections can cause inflammation of the colon and stomach, causing diarrhea that may contain mucus and blood. Viral gastroenteritis does not typically cause bloody diarrhea.

Treatment for gastroenteritis usually involves fluids, rest, and antibiotics or antivirals, depending on the exact cause.

7. Sexually transmitted infections (STIs)

Unprotected sexual intercourse that involves the anal area can spread a wide range of viral and bacterial diseases. These can cause inflammation of the anus and rectum. Inflammation, if it occurs, increases the likelihood of bleeding.

Treatment for STIs usually involves either an antibiotic, antiviral, or antifungal medication based on the type of infection.

8. Prolapse

Weakened rectal tissues can allow a portion of the rectum to push forward or bulge outside of the anus, usually resulting in pain and, almost always, bleeding.

Rectal prolapse can occur at any age; however, females over the age of 50 have a 6 times higher risk of developing a prolapse compared with males.

Typical treatment involves surgical intervention.

9. Polyps

Polyps are noncancerous, abnormal growths. When polyps grow on the lining of the rectum or colon they can cause irritation, inflammation, and minor bleeding.

In many cases, a doctor will typically remove polyps during a routine colonoscopy screening.

10. Colon or rectal cancer

Cancer that impacts the colon or rectum can cause irritation, inflammation, and bleeding. The blood may appear bright red or can cause stool to have a darker color.

Colon cancer is a very common form of cancer and tends to progress slowly, so it is often treatable if caught early.

Rectal cancer, while far rarer than colon cancer, is also usually curable if detected and treated in time.

Some cases of colon and rectal cancer develop from initially benign polyps. All cases of gastrointestinal cancer require treatment, which varies based on the stage of the cancer but can involve surgery or a combination of chemotherapy, radiation therapy, and surgery.

11. Internal bleeding

Major injury to any of the gastrointestinal organs can result in internal bleeding that passes through the rectum. Severe gastrointestinal disease can also lead to internal bleeding.

A person should see their doctor if they suspect internal rectal bleeding. The doctor will likely order a colonoscopy.

Occasional minor to mild rectal bleeding is common and will often not need medical attention or treatment.

Severe, chronic, or painful rectal bleeding may be a sign of a more serious underlying condition, which a doctor should assess.

People normally notice rectal bleeding when they see streaks or drips of blood in their stool, the toilet bowl, or when wiping. Some people may also find blood in their underwear, or the toilet water may appear reddish-pink after they go to the bathroom.

Some cases of rectal bleeding also cause very bad smelling, dark, tarry stool mixed with dark red to black blood.

Reasons to see a doctor for rectal bleeding include:

  • bleeding that lasts longer than a few days
  • children with bloody stool or rectal bleeding
  • unexplained weight loss, fatigue, or weakness
  • painful, swollen, or tender abdomen
  • accompanying fever
  • simultaneous lumps in the abdomen
  • stool that is thinner, longer, or softer than normal for several weeks
  • accompanying nausea or vomiting
  • accompanying long-term constipation or changes in bowel habits
  • associated uncontrolled leakage from the anus

Reasons to seek emergency care for rectal bleeding include:

  • heavy bleeding
  • vomiting or coughing up blood
  • blood running from the nose, eyes, or ears
  • bleeding that is very dark red or black
  • the reason for bloody diarrhea is unclear, such as unrelated to an abdominal condition or medical treatment
  • loss of consciousness or confusion
  • extreme abdominal or lower back pain

If bleeding is associated with an already diagnosed medical condition, a doctor will discuss ways to manage, reduce, and track symptoms.

If the cause of rectal bleeding is unknown, a doctor will normally ask questions about symptoms and the person’s medical history.

Depending on the severity, frequency, and accompanying symptoms, the doctor will work out if further testing is required. A doctor may also make a referral to a gastrointestinal or colorectal specialist.

Common tests associated with rectal bleeding include:

  • a physical examination of the anus and rectum
  • analysis of a stool sample

Specialists may perform additional tests that can include:

  • colonoscopy or flexible sigmoidoscopy, where the doctor examines the colon with the insertion of a tube with a camera
  • anoscopy, where a doctor inserts a device into the anus to examine the tissue
  • biopsy or removal of a small tissue sample for examination
  • computerized tomography (CT) scan, which provides a 3D image

In some cases, there is no real way to prevent minor cases of rectal bleeding. However, some factors are known to cause, contribute to, or worsen anal bleeding.

Common prevention tips for rectal, colon and anal bleeding include:

  • eating a balanced diet that is high in fiber
  • always staying hydrated
  • not straining when going to the washroom
  • wiping the anus gently
  • treating chronic or prolonged constipation with OTC remedies, such as stool softeners
  • treating chronic or prolonged diarrhea with OTC remedies, such as bismuth subsalicylate
  • trying not to lift heavy objects unless required
  • maintaining a healthy body weight
  • taking long, warm baths frequently if experiencing symptoms
  • following treatment plans set out by a doctor for related medical conditions
  • trying to avoid spicy, rich, fatty, heavily processed, and refined foods
  • seeing a doctor about abnormal growths in the area
  • avoiding overuse of nonsteroidal anti-inflammatory drugs (NSAIDs)
  • wearing a condom during anal sex

People may wish to talk with a doctor about gastrointestinal symptoms that may be a sign of underlying conditions, including infections, digestive conditions, or abnormal growths.

Treatment for blood in the stool or when wiping depends on the exact cause of the bleeding.

For example, OTC and prescription creams can often treat hemorrhoids, while a diet rich in fiber or surgery may help with diverticulitis.

Common treatments include:

  • antibiotics
  • topical creams or ointments
  • eating more fiber
  • procedures such as a colonoscopy, or, in some cases, surgery to remove part of the colon

A person should talk with their doctor about what treatment options work best for them.

Some people may avoid talking with their doctor about rectal bleeding, even in moderate or severe cases, because they are embarrassed or have anxiety. While rare, heavy or chronic rectal bleeding can cause serious blood loss or be a sign of an underlying condition that requires treatment.

People should see a doctor about rectal bleeding that is chronic or noticeable or if they notice abnormal growths around the anus.

People should seek emergency medical attention for anal bleeding or stool that is very dark, especially if they are also vomiting or coughing up blood. It is also vital to seek immediate help for bleeding that lasts for more than a few minutes or if there are also other symptoms, such as severe pain, fever, or weakness.

The answers to some commonly asked questions appear below.

Why is there blood when I wipe?

Several underlying conditions can cause blood when a person wipes. The reasons can range from benign conditions, such as hemorrhoids or a minor injury, to much more severe conditions, such as cancer.

Why is there a small amount of blood when wiping?

A small amount of blood may indicate the presence of hemorrhoids or another minor issue. A small amount of blood may not require any specialized care or attention. However, if it gets worse or does not go away within a few days, a person should talk with their doctor.

Why is there blood when I wipe, but not in the stool and no pain?

The color of blood when wiping and the presence of blood in a person’s stool can help determine where the bleeding originates. As a general rule, if a person notices bright, red blood when wiping, it indicates the bleeding occurs near the rectum, while darker blood or bloody stool indicates the bleeding occurs further into the intestine. If bleeding occurs, a person should consider seeing their doctor if it is severe, worsens, or continues for several days.

Many times, a small amount of blood in the stool or when wiping is not a reason for concern. However, in some cases, it could mean bleeding in the rectum or colon. If the blood is very dark, this could mean the bleeding is coming from the digestion system.

There are numerous, possible causes of rectal symptoms. Each one may have different additional symptoms. If a person finds bleeding in the toilet after a bowel movement or when wiping, it is a good idea to see a doctor to rule out any serious conditions.

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