Blood in the stool can be bright red, maroon in color, black and tarry, or occult (not visible to the naked eye). Causes of blood in the stool range from harmless, annoying conditions of the gastrointestinal tract such as hemorrhoids and anal tears (anal fissures) from straining against hard stools with constipation to serious conditions such as cancer. Blood in the stool should be evaluated by a health care professional.
Rectal bleeding (known medically as hematochezia) refers to passage of bright red blood from the anus, often mixed with stool and/or blood clots. Most rectal bleeding comes from the colon, rectum, or anus and can be associated with diarrhea. The color of the blood during rectal bleeding often depends on the location of the bleeding in the gastrointestinal tract. Generally, the closer the bleeding site is to the anus, the blood will be a brighter red. Thus, bleeding from the anus, rectum, and the sigmoid colon tend to be bright red, whereas bleeding from the transverse colon and the right colon (transverse and right colon are several feet away from the anus) tend to be dark red or maroon colored.
In some patients, bleeding can be black and "tarry" (sticky) and foul smelling. The black, smelly, and tarry stool is called melena. Melena occurs when the blood is in the colon long enough for the bacteria in the colon to break it down into chemicals (hematin) that are black. Therefore, melena usually signifies bleeding is from the upper gastrointestinal tract (for example, bleeding from ulcers in the stomach or the duodenum or from the small intestine) because the blood usually is in the gastrointestinal tract for a longer period of time before it exits the body. Sometimes melena may occur with bleeding from the right colon. On the other hand, blood from the sigmoid colon and the rectum usually does not stay in the colon long enough for the bacteria to turn it black. Rarely, massive bleeding from the right colon, from the small intestine, or from ulcers of the stomach or duodenum can cause rapid transit of the blood through the gastrointestinal tract and result in bright red rectal bleeding. In these situations, the blood is moving through the colon so rapidly that there is not enough time for the bacteria to turn the blood black.
Sometimes, bleeding from the gastrointestinal tract can be too slow to cause either rectal bleeding or melena. In these patients, bleeding is occult (not visible to the naked eye). The blood is found only by testing the stool for blood (fecal occult blood testing) in the laboratory. Occult bleeding has many of the same causes as rectal bleeding and may result in the same symptoms as rectal bleeding. It is often associated with anemia that is due to loss of iron along with the blood (iron deficiency anemia).
Causes of rectal bleeding include hemorrhoids, anal fissure, proctitis, Crohn's disease, diverticulosis, ulcerative colitis, rectal ulcer, rectal prolapse, ischemic colitis, angiodysplasia, rectal trauma, anal cancer, colon cancer, proctitis from radiation therapy, and others.
For more information, please see the colon cancer screening and fecal occult blood test articles.
Other causes of rectal bleeding
- Esophageal Varices
Causes of Rectal Bleeding
H. pylori (Helicobacter Pylori) Infection
Helicobacter pylori (H. pylori) is a bacteria that causes chronic inflammation (gastritis) of the inner lining of the stomach, and also is the most common cause of ulcers worldwide. About 50% of people in the world carries or is infected with H. pylori. Common symptoms of H. pylori infection are occasional abdominal discomfort, bloating, belching or burping, and nausea and vomiting. H. pylori infection is difficult to eradicate, and treatment is with two or more antibiotics.
Amebiasis (Entamoeba Histolytica Infection)
Amebiasis is an infection caused by an amoeba. Signs and symptoms include bloody stools, abdominal pain, weight loss, fever, and gas. Treatment may involve taking luminal agents or antibiotics. Surgery may be indicated for various reasons.
Anal cancer, cancer located at the end of the large intestine, has symptoms that include anal or rectal bleeding, anal pain or pressure, anal discharge or itching, a change in bowel movements, and/or a lump in the anal region. Treatment for anal cancer may involve radiation, chemotherapy, or surgery and depends upon the stage of the cancer, its location, whether cancer is eradicated after the first treatment, and whether the patient has HIV.Anal cancer is usually curable when found localized. Early detection remains the key to long-term survival as it is in many forms of cancer.
An anal fissure is a small tear or cut in the skin lining of the anus. Pain and/or rectal bleeding during bowel movements are common symptoms of anal fissures. Treatment includes increasing liquid intake, using stool softeners, prescription medications, and surgery.
Blood in the Stool (Rectal Bleeding, Hematochezia)
Blood in the stool or rectal bleeding (hematochezia) refers to the passage of bright red blood from the anus. Common causes include anal fissures, hemorrhoids, diverticulitis, colitis, Crohn's disease, colon and rectum polyps, and cancer. The color of the blood in the stool may provide information about the origin of the bleeding. The color of stool with blood in it may range from black, red, maroon, green yellow, gray, or white, and may be tarry, or sticky. Treatment of blood in the stool depends on the cause.
Can You Pop a Hemorrhoid?
Hemorrhoids or piles are swollen, inflamed veins around the anus or lower part of the rectum (the terminal part of the large bowel). They often get better on their own within a few days, but some may need medications and even surgery to go away. You must not pop a hemorrhoid because doing so can lead to painful and serious complications. You must always consult your doctor for a definitive diagnosis and treatment.
Colitis refers to inflammation of the inner lining of the colon. Symptoms of the inflammation of the colon lining include diarrhea, pain, and blood in the stool. There are several causes of colitis, including infection, ischemia of the colon, inflammatory bowel disease (Crohn's disease, ulcerative colitis, infectious colitis like C. difficile, or microscopic colitis). Treatment depends on the cause of the colitis.
Colon cancer (bowel cancer) is a malignancy that arises from the inner lining of the colon. Most, if not all, of these cancers develop from colonic polyps. Removal of these precancerous polyps can prevent colon cancer.
Colon Polyps: Symptoms, Causes, Cancer Risk, Treatment, and Prevention
Colon polyps are common growths on the inner lining of the colon. Colon polyps may become cancerous. There are several different types of colon polyps, and the chance of the polyp becoming cancerous depends on the type, size, and histology. Blood in the stool or rectal bleeding are the most common symptoms of colon polyps. Treatment for colon polyps depend on the type, size, and histology.
Crohn's Disease vs. Ulcerative Colitis (UC)
Crohn's disease and ulcerative colitis are diseases that cause inflammation of part of or the entire digestive tract (GI). Crohn's affects the entire GI tract (from the mouth to the anus), while ulcerative colitis or ulcerative colitis only affects the large and small intestine and ilium. Researchers do not know the exact cause of either disease. About 20% of people with Crohn's disease also have a family member with the disease. Researchers believe that certain factors may play a role in causing UC. Both Crohn's disease and ulcerative colitis are a type of inflammatory bowel disease, or IBD. Crohn's disease and ulcerative colitis both have similar symptoms and signs, for example, nausea, loss of appetite, fatigue, weight loss, episodic and/or persistent diarrhea, fever, abdominal pain and cramping, rectal bleeding, bloody stools, joint pain and soreness, eye redness, or pain. Symptoms unique to Crohn’s disease include anemia and skin changes. Symptoms of unique to ulcerative colitis include, certain rashes, an urgency to defecate (have a bowel movement). Doctors diagnose both diseases with similar tests and procedures. While there is no cure for either disease, doctors and other health care professionals can help you treat disease flares, and manage your Crohn's or ulcerative colitis with medication, diet, nutritional supplements, and/or surgery.
Diverticulitis (Diverticulosis, Diverticular Disease)
Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis (diverticular disease) they may include abdominal pain, abdominal cramps, diarrhea, constipation, and bloating. Diverticulitis is a condition in which diverticuli in the colon rupture. The rupture results in infection in the tissues that surround the colon. Treatment methods for diverticulitis includes prescription medications, and in some cases, diverticulitis surgery.
Gastroesophageal Junction Adenocarcinoma
Gastroesophageal junction adenocarcinoma is cancer that forms in the area where the esophagus joins the stomach. Having GERD and Barrett's esophagus increases one's odds of developing gastroesophageal junction adenocarcinoma. Symptoms and signs of GE junction adenocarcinoma include dysphagia, weight loss, black stool, cough, nausea, and vomiting. Treatment may include surgery, chemotherapy, radiation therapy, immunotherapy, and targeted therapy.
Hemorrhoids (piles) are swollen veins in the rectum and anus. Causes include pregnancy, obesity, diarrhea, low-fiber diet, and prolonged sitting on the toilet. Treatment varies depending upon the severity of the hemorrhoids. Some treatment options include over-the-counter creams and suppositories, stool softeners, warm sitz baths, and hemorrhoidectomies.
How Do You Know If You Have Rectal Prolapse?
Rectal prolapse is a common issue that affects many people. Learn the signs of rectal prolapse, what causes it, how doctors diagnose it, and what you can do to treat it.
Idiopathic Thrombocytopenic Purpura (ITP)
Idiopathic means that the cause of the condition isn't known. Thrombocytopenic means there's a lower than normal number of platelets in the blood. Purpura refers to purple bruises caused by bleeding under the skin. Idiopathic thrombocytopenic purpura (ITP) is a bleeding condition in which the blood doesn't clot as it should. This is due to a low number of blood cell fragments called platelets.
Internal bleeding occurs when an artery or vein is damaged and blood to escapes the circulatory system and collects inside the body. Internal bleeding can be caused by a variety of situations such as blunt trauma, deceleration trauma, medications, fractures, and spontaneous bleeding. Treatment of internal bleeding depends on the cause of the bleeding.
Is C. diff (Clostridium difficile) Contagious?
C. diff, or Clostridium difficile, is a bacteria that infects the colon. C. diff bacteria can be found on furniture, bathroom floors, telephones, fingernails, jewelry, toilet seats, and other places. Symptoms of C. diff infection are fever, abdominal pain, and cramps; however, not all people infected with C. diff have symptoms. Treatments for C. diff are antibiotics and surgery in some cases.
Is Bright Red Blood in the Stool Serious?
The presence of blood in the stool needs to be evaluated by your doctor. In most cases, the bright red blood in stools is not an immediate threat to life. The most common causes are piles, anal polyps, anal fissures and colitis (inflammation of the large bowel).
Is Cancer Contagious?
Cancer is an abnormal growth of cells. A variety of parasites and viruses have been linked to various cancers. Cancer may metastasize, spreading from its original location to other organs. If you have cancer, you should seek medical care immediately if you experience high fever, shortness of breath, intense headaches, vomiting blood or passing blood rectally, chest pain or moderate to severe weakness, passing out (fainting), mental status changes, or seizures.
Is Colitis Contagious?
Colitis is a term that us used to describe inflammation of the colon. The terms enteritis, proctitis, and inflammatory bowel disease (IBD) now include colitis. Colitis has many different causes. Some types of colitis are contagious and some are not contagious. Symptoms and signs of colitis include diarrhea, abdominal discomfort, cramping, pain, and blood in the stools. Treatment for colitis depends on the cause and type of colitis.
Is H. pylori Contagious?
H. pylori (Helicobacter pylori) infection: Is it contagious? H. pylori infection is caused by fecal contamination in either food or water, and by poor hygiene practices such as not washing the hands often. Common symptoms of H. pylori are a discomfort or pain in the area of the stomach. Some individuals describe the pain as gnawing or burning. Treatment of H. pylori infection is antibiotic therapy.
Peptic Ulcer (Stomach Ulcer)
Peptic or stomach ulcers are ulcers are an ulcer in the lining of the stomach, duodenum, or esophagus. Ulcer formation is related to H. pylori bacteria in the stomach, use of anti-inflammatory medications, and cigarette smoking. Symptoms of peptic or stomach ulcers include abdominal burning or hunger pain, indigestion, and abdominal discomfort after meals. Treatment for stomach ulcers depends upon the cause.
STDs in Men
Sexually transmitted diseases (STDs) are infections transmitted during sexual contact. They may be caused by viruses, bacteria, or parasites. STDs in men cause no symptoms or symptoms like genital burning, itching, sores, rashes, or discharge. Common infections that are sexually transmitted in men include gonorrhea, chlamydia, syphilis, hepatitis C and B, genital warts, human papillomavirus (HPV), and genital herpes. Some STDs in men are treatable while others are not. STDs are diagnosed with tests that identify proteins or genetic material of the organisms causing the infection. The prognosis of an STD depends on whether the infection is treatable or not. Use of latex condoms can help reduce the risk of contracting an STD but it does not eliminate the risk entirely.
Though the cause of stomach cancer is unknown, risk factors for stomach cancer include diet, H. pylori infection, smoking age, gastritis, stomach surgery, family history, and pernicious anemia. Symptoms include stomach discomfort, feeling full after a small meal, nausea and vomiting, and weight loss. Treatment depends upon staging and may involve surgery, radiation therapy, or chemotherapy.
Stool Color, Changes in Color, Texture, and Form
Stool color changes can very from green, red, maroon, yellow, white, or black. Causes of changes of stool color can range from foods a person eats, medication, diseases or conditions, pregnancy, cancer, or tumors. Stool can also have texture changes such as greasy or floating stools. Stool that has a uncharacteristically foul odor may be caused by infections such as giardiasis or medical conditions.
What Is Crohn's Disease?
Crohn's disease is a chronic inflammatory disease, primarily involving the small and large intestine, but which can affect other parts of the digestive system as well. Abdominal pain, diarrhea, vomiting, fever, and weight loss are common symptoms.
What Is the Main Cause of Esophageal Varices?
Esophageal varices are enlarged veins in the food pipe (esophagus). This condition develops in people with liver disease.
When Should I Be Concerned About Blood in My Stool?
Blood in the stool can be a symptom of many disorders, some of which may be serious. Learn the signs of blood in the stool, what causes it, how doctors diagnose it, and what you can do to treat it.
Yellow fever is an infectious disease transmitted by infected mosquitoes. Side effects are rare with the yellow fever vaccine. Symptoms include fever, chills, back pain, nausea, vomiting, and headache. Treatment is aimed at relieving symptoms.